Organelles
Organoids
Mitochondria
Microscopy, Electron
Lysosomes
Golgi Apparatus
Endoplasmic Reticulum
Autophagy
Vacuoles
Protein Transport
Intracellular Membranes
Peroxisomes
Microtubules
Endosomes
Biological Transport
Cell Fractionation
Plastids
Membrane Proteins
Kinesin
Cytoplasm
Subcellular Fractions
Microscopy, Fluorescence
Phagosomes
Molecular Sequence Data
Chloroplasts
Cell Compartmentation
Cytoplasmic Vesicles
Cytoplasmic Streaming
Cilia
Cell Membrane
Models, Biological
Axonal Transport
Melanophores
Microscopy, Immunoelectron
Microscopy, Electron, Transmission
rab GTP-Binding Proteins
Amino Acid Sequence
Endocytosis
Microtubule-Associated Proteins
Dyneins
Transport Vesicles
Green Fluorescent Proteins
Cell Nucleus
Microbodies
Mitochondrial Proteins
Eukaryotic Cells
Myosin Type V
Microscopy, Confocal
Eukaryota
Mutation
Secretory Vesicles
Saccharomyces cerevisiae
Vacuolar Proton-Translocating ATPases
Cytoskeleton
Cytosol
Molecular Motor Proteins
Luminescent Proteins
Vesicular Transport Proteins
Flagella
Cells, Cultured
Recombinant Fusion Proteins
Chlorophyta
Mitochondrial Membranes
Lysosome-Associated Membrane Glycoproteins
Blastocystis
Membrane Fusion
Secretory Pathway
Fluorescent Antibody Technique
Mitochondrial Dynamics
Carrier Proteins
Saccharomyces cerevisiae Proteins
Brefeldin A
Inclusion Bodies
DNA, Mitochondrial
Weibel-Palade Bodies
Calcium
Arabidopsis
Plants
Endoplasmic Reticulum, Smooth
Centrifugation, Density Gradient
Cell Biology
Adenosine Triphosphate
Exocytosis
Proteins
Actin Cytoskeleton
Magnetosomes
HeLa Cells
Fluorescent Dyes
Hydrogen-Ion Concentration
Plant Proteins
Histocytochemistry
Protein Binding
Actins
Sequence Homology, Amino Acid
Decapodiformes
Signal Transduction
trans-Golgi Network
Electron Microscope Tomography
Centrioles
Apicomplexa
Potassium Iodide
Toxoplasma
Propylene Glycol
Lipid Metabolism
Arabidopsis Proteins
Base Sequence
Protein Structure, Tertiary
Acridine Orange
Multivesicular Bodies
Sequence Alignment
Protein Sorting Signals
Melanocytes
Acid Phosphatase
Mitochondria, Liver
Nocodazole
Magnetospirillum
Tubulin
Ciliophora
Trypanosoma brucei brucei
Adenosine Triphosphatases
Rhodophyta
Movement
Liver
Chediak-Higashi Syndrome
Immunoblotting
Microscopy, Electron, Scanning
Centrifugation
Microscopy, Video
Neurons
Biological Transport, Active
Cloning, Molecular
Microscopy, Phase-Contrast
Cytochalasins
Proton Pumps
Synaptic Vesicles
Propanediol Dehydratase
Macrolides
Microscopy
Centrosome
Blotting, Western
Mycoplasma pneumoniae
Protein Processing, Post-Translational
Homeostasis
Synaptophysin
Phenotype
Cercozoa
Evolution, Molecular
Immunohistochemistry
Endoplasmic Reticulum, Rough
Staining and Labeling
Time-Lapse Imaging
Mesophyll Cells
Association of snRNA genes with coiled bodies is mediated by nascent snRNA transcripts. (1/2526)
BACKGROUND: Coiled bodies are nuclear organelles that are highly enriched in small nuclear ribonucleoproteins (snRNPs) and certain basal transcription factors. Surprisingly, coiled bodies not only contain mature U snRNPs but also associate with specific chromosomal loci, including gene clusters that encode U snRNAs and histone messenger RNAs. The mechanism(s) by which coiled bodies associate with these genes is completely unknown. RESULTS: Using stable cell lines, we show that artificial tandem arrays of human U1 and U2 snRNA genes colocalize with coiled bodies and that the frequency of the colocalization depends directly on the transcriptional activity of the array. Association of the genes with coiled bodies was abolished when the artificial U2 arrays contained promoter mutations that prevent transcription or when RNA polymerase II transcription was globally inhibited by alpha-amanitin. Remarkably, the association was also abolished when the U2 snRNA coding regions were replaced by heterologous sequences. CONCLUSIONS: The requirement for the U2 snRNA coding region indicates that association of snRNA genes with coiled bodies is mediated by the nascent U2 RNA itself, not by DNA or DNA-bound proteins. Our data provide the first evidence that association of genes with a nuclear organelle can be directed by an RNA and suggest an autogenous feedback regulation model. (+info)Hsp60 is targeted to a cryptic mitochondrion-derived organelle ("crypton") in the microaerophilic protozoan parasite Entamoeba histolytica. (2/2526)
Entamoeba histolytica is a microaerophilic protozoan parasite in which neither mitochondria nor mitochondrion-derived organelles have been previously observed. Recently, a segment of an E. histolytica gene was identified that encoded a protein similar to the mitochondrial 60-kDa heat shock protein (Hsp60 or chaperonin 60), which refolds nuclear-encoded proteins after passage through organellar membranes. The possible function and localization of the amebic Hsp60 were explored here. Like Hsp60 of mitochondria, amebic Hsp60 RNA and protein were both strongly induced by incubating parasites at 42 degreesC. 5' and 3' rapid amplifications of cDNA ends were used to obtain the entire E. histolytica hsp60 coding region, which predicted a 536-amino-acid Hsp60. The E. histolytica hsp60 gene protected from heat shock Escherichia coli groEL mutants, demonstrating the chaperonin function of the amebic Hsp60. The E. histolytica Hsp60, which lacked characteristic carboxy-terminal Gly-Met repeats, had a 21-amino-acid amino-terminal, organelle-targeting presequence that was cleaved in vivo. This presequence was necessary to target Hsp60 to one (and occasionally two or three) short, cylindrical organelle(s). In contrast, amebic alcohol dehydrogenase 1 and ferredoxin, which are bacteria-like enzymes, were diffusely distributed throughout the cytosol. We suggest that the Hsp60-associated, mitochondrion-derived organelle identified here be named "crypton," as its structure was previously hidden and its function is still cryptic. (+info)A novel interaction mechanism accounting for different acylphosphatase effects on cardiac and fast twitch skeletal muscle sarcoplasmic reticulum calcium pumps. (3/2526)
In cardiac and skeletal muscle Ca2+ translocation from cytoplasm into sarcoplasmic reticulum (SR) is accomplished by different Ca2+-ATPases whose functioning involves the formation and decomposition of an acylphosphorylated phosphoenzyme intermediate (EP). In this study we found that acylphosphatase, an enzyme well represented in muscular tissues and which actively hydrolyzes EP, had different effects on heart (SERCA2a) and fast twitch skeletal muscle SR Ca2+-ATPase (SERCA1). With physiological acylphosphatase concentrations SERCA2a exhibited a parallel increase in the rates of both ATP hydrolysis and Ca2+ transport; in contrast, SERCA1 appeared to be uncoupled since the stimulation of ATP hydrolysis matched an inhibition of Ca2+ pump. These different effects probably depend on phospholamban, which is associated with SERCA2a but not SERCA1. Consistent with this view, the present study suggests that acylphosphatase-induced stimulation of SERCA2a, in addition to an enhanced EP hydrolysis, may be due to a displacement of phospholamban, thus to a removal of its inhibitory effect. (+info)Rational analyses of organelle trajectories in tobacco pollen tubes reveal characteristics of the actomyosin cytoskeleton. (4/2526)
To gain insight into the characteristics of organelle movement and the underlying actomyosin motility system in tobacco pollen tubes, we collected data points representing sequential organelle positions in control and cytochalasin-treated cells, and in a sample of extruded cytoplasm. These data were utilized to reconstruct approximately 900 tracks, representing individual organelle movements, and to produce a quantitative analysis of the movement properties, supported by statistical tests. Each reconstructed track appeared to be unique and to show irregularities in velocity and direction of movement. The regularity quotient was near 2 at the tip and above 3 elsewhere in the cell, indicating that movement is more vectorial in the tube area. Similarly, the progressiveness ratio showed that there were relatively more straight trajectories in the tube region than at the tip. Consistent with these data, arithmetical dissection revealed a high degree of randomlike movement in the apex, lanes with tip-directed movement along the flanks, and grain-directed movement in the center of the tube. Intercalated lanes with bidirectional movement had lower organelle velocity, suggesting that steric hindrance plays a role. The results from the movement analysis indicate that the axial arrangement of the actin filaments and performance of the actomyosin system increases from tip to base, and that the opposite polarity of the actin filaments in the peripheral (+-ends of acting filaments toward the tip) versus the central cytoplasm (+-ends of actin filaments toward to the grain) is installed within a few minutes in these tip-growing cells. (+info)Redundant systems of phosphatidic acid biosynthesis via acylation of glycerol-3-phosphate or dihydroxyacetone phosphate in the yeast Saccharomyces cerevisiae. (5/2526)
In the yeast Saccharomyces cerevisiae lipid particles harbor two acyltransferases, Gat1p and Slc1p, which catalyze subsequent steps of acylation required for the formation of phosphatidic acid. Both enzymes are also components of the endoplasmic reticulum, but this compartment contains additional acyltransferase(s) involved in the biosynthesis of phosphatidic acid (K. Athenstaedt and G. Daum, J. Bacteriol. 179:7611-7616, 1997). Using the gat1 mutant strain TTA1, we show here that Gat1p present in both subcellular fractions accepts glycerol-3-phosphate and dihydroxyacetone phosphate as a substrate. Similarly, the additional acyltransferase(s) present in the endoplasmic reticulum can acylate both precursors. In contrast, yeast mitochondria harbor an enzyme(s) that significantly prefers dihydroxyacetone phosphate as a substrate for acylation, suggesting that at least one additional independent acyltransferase is present in this organelle. Surprisingly, enzymatic activity of 1-acyldihydroxyacetone phosphate reductase, which is required for the conversion of 1-acyldihydroxyacetone phosphate to 1-acylglycerol-3-phosphate (lysophosphatidic acid), is detectable only in lipid particles and the endoplasmic reticulum and not in mitochondria. In vivo labeling of wild-type cells with [2-3H, U-14C]glycerol revealed that both glycerol-3-phosphate and dihydroxyacetone phosphate can be incorporated as a backbone of glycerolipids. In the gat1 mutant and the 1-acylglycerol-3-phosphate acyltransferase slc1 mutant, the dihydroxyacetone phosphate pathway of phosphatidic acid biosynthesis is slightly preferred as compared to the wild type. Thus, mutations of the major acyltransferases Gat1p and Slc1p lead to an increased contribution of mitochondrial acyltransferase(s) to glycerolipid synthesis due to their substrate preference for dihydroxyacetone phosphate. (+info)Surface proteins of gram-positive bacteria and mechanisms of their targeting to the cell wall envelope. (6/2526)
The cell wall envelope of gram-positive bacteria is a macromolecular, exoskeletal organelle that is assembled and turned over at designated sites. The cell wall also functions as a surface organelle that allows gram-positive pathogens to interact with their environment, in particular the tissues of the infected host. All of these functions require that surface proteins and enzymes be properly targeted to the cell wall envelope. Two basic mechanisms, cell wall sorting and targeting, have been identified. Cell well sorting is the covalent attachment of surface proteins to the peptidoglycan via a C-terminal sorting signal that contains a consensus LPXTG sequence. More than 100 proteins that possess cell wall-sorting signals, including the M proteins of Streptococcus pyogenes, protein A of Staphylococcus aureus, and several internalins of Listeria monocytogenes, have been identified. Cell wall targeting involves the noncovalent attachment of proteins to the cell surface via specialized binding domains. Several of these wall-binding domains appear to interact with secondary wall polymers that are associated with the peptidoglycan, for example teichoic acids and polysaccharides. Proteins that are targeted to the cell surface include muralytic enzymes such as autolysins, lysostaphin, and phage lytic enzymes. Other examples for targeted proteins are the surface S-layer proteins of bacilli and clostridia, as well as virulence factors required for the pathogenesis of L. monocytogenes (internalin B) and Streptococcus pneumoniae (PspA) infections. In this review we describe the mechanisms for both sorting and targeting of proteins to the envelope of gram-positive bacteria and review the functions of known surface proteins. (+info)Rat liver GTP-binding proteins mediate changes in mitochondrial membrane potential and organelle fusion. (7/2526)
The variety of mitochondrial morphology in healthy and diseased cells can be explained by regulated mitochondrial fusion. Previously, a mitochondrial outer membrane fraction containing fusogenic, aluminum fluoride (AlF4)-sensitive GTP-binding proteins (mtg) was separated from rat liver (J. D. Cortese, Exp. Cell Res. 240: 122-133, 1998). Quantitative confocal microscopy now reveals that mtg transiently increases mitochondrial membrane potential (DeltaPsi) when added to permeabilized rat hepatocytes (15%), rat fibroblasts (19%), and rabbit myocytes (10%). This large mtg-induced DeltaPsi increment is blocked by fusogenic GTPase-specific modulators such as guanosine 5'-O-(3-thiotriphosphate), excess GTP (>100 microM), and AlF4, suggesting a linkage between DeltaPsi and mitochondrial fusion. Accordingly, stereometric analysis shows that decreasing DeltaPsi or ATP synthesis with respiratory inhibitors limits mtg- and AlF4-induced mitochondrial fusion. Also, a specific G protein inhibitor (Bordetella pertussis toxin) hyperpolarizes mitochondria and leads to a loss of AlF4-dependent mitochondrial fusion. These results place mtg-induced DeltaPsi changes upstream of AlF4-induced mitochondrial fusion, suggesting that GTPases exert DeltaPsi-dependent control of the fusion process. Mammalian mitochondrial morphology thus can be modulated by cellular energetics. (+info)Occurrence of prostasome-like membrane vesicles in equine seminal plasma. (8/2526)
Equine seminal plasma was shown to contain membrane vesicles that are similar to the well characterized prostasomes in human seminal plasma. Determination of nucleoside and nucleotide concentrations of these particles have shown that ATP, ADP and adenosine are the main components of the nucleotidic pool. 5' nucleotidase, endopeptidase and dipeptidyl peptidase i.v. activities have been found on the surface of the particles. The interaction between these prostasome-like vesicles and spermatozoa was demonstrated by electron micrograph scans which revealed the steps of a fusion-like process leading to mixing of the membranes. In addition, endopeptidase activity, a marker enzyme of these seminal vesicles that is normally absent from equine spermatozoa, was shown to be acquired by these cells after interaction with the vesicles. The addition of these vesicles to equine spermatozoa resulted in the modification of adenylate catabolism. Therefore, a role in stabilizing the energy charge of the spermatozoa thus allowing longer viability is proposed for these organelles. (+info)Organelles are specialized structures within cells that perform specific functions essential for the cell's survival and proper functioning. They can be thought of as the "organs" of the cell, and they are typically membrane-bound to separate them from the rest of the cellular cytoplasm. Examples of organelles include the nucleus (which contains the genetic material), mitochondria (which generate energy for the cell), ribosomes (which synthesize proteins), endoplasmic reticulum (which is involved in protein and lipid synthesis), Golgi apparatus (which modifies, sorts, and packages proteins and lipids for transport), lysosomes (which break down waste materials and cellular debris), peroxisomes (which detoxify harmful substances and produce certain organic compounds), and vacuoles (which store nutrients and waste products). The specific organelles present in a cell can vary depending on the type of cell and its function.
Organoids are 3D tissue cultures grown from stem cells that mimic the structure and function of specific organs. They are used in research to study development, disease, and potential treatments. The term "organoid" refers to the fact that these cultures can organize themselves into structures that resemble rudimentary organs, with differentiated cell types arranged in a pattern similar to their counterparts in the body. Organoids can be derived from various sources, including embryonic stem cells, induced pluripotent stem cells (iPSCs), or adult stem cells, and they provide a valuable tool for studying complex biological processes in a controlled laboratory setting.
I'm sorry for any confusion, but "Organelle Size" is not a recognized medical term or concept with a specific definition. Organelles are specialized structures within cells that have specific functions, such as mitochondria, ribosomes, and endoplasmic reticulum. The size of these organelles can vary depending on the type of cell, its function, and various other factors. However, there is no standardized medical definition for the term "Organelle Size." If you have more specific questions about the size or function of certain organelles, I'd be happy to help further!
Mitochondria are specialized structures located inside cells that convert the energy from food into ATP (adenosine triphosphate), which is the primary form of energy used by cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of chemical energy. Mitochondria are also involved in various other cellular processes, such as signaling, differentiation, and apoptosis (programmed cell death).
Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is inherited maternally. This means that mtDNA is passed down from the mother to her offspring through the egg cells. Mitochondrial dysfunction has been linked to a variety of diseases and conditions, including neurodegenerative disorders, diabetes, and aging.
Electron microscopy (EM) is a type of microscopy that uses a beam of electrons to create an image of the sample being examined, resulting in much higher magnification and resolution than light microscopy. There are several types of electron microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and reflection electron microscopy (REM).
In TEM, a beam of electrons is transmitted through a thin slice of the sample, and the electrons that pass through the sample are focused to form an image. This technique can provide detailed information about the internal structure of cells, viruses, and other biological specimens, as well as the composition and structure of materials at the atomic level.
In SEM, a beam of electrons is scanned across the surface of the sample, and the electrons that are scattered back from the surface are detected to create an image. This technique can provide information about the topography and composition of surfaces, as well as the structure of materials at the microscopic level.
REM is a variation of SEM in which the beam of electrons is reflected off the surface of the sample, rather than scattered back from it. This technique can provide information about the surface chemistry and composition of materials.
Electron microscopy has a wide range of applications in biology, medicine, and materials science, including the study of cellular structure and function, disease diagnosis, and the development of new materials and technologies.
Lysosomes are membrane-bound organelles found in the cytoplasm of eukaryotic cells. They are responsible for breaking down and recycling various materials, such as waste products, foreign substances, and damaged cellular components, through a process called autophagy or phagocytosis. Lysosomes contain hydrolytic enzymes that can break down biomolecules like proteins, nucleic acids, lipids, and carbohydrates into their basic building blocks, which can then be reused by the cell. They play a crucial role in maintaining cellular homeostasis and are often referred to as the "garbage disposal system" of the cell.
I'm sorry for any confusion, but "organelle shape" is not a medical term with a specific definition. Organelles are specialized structures within cells that have specific functions, and they can vary in shape between different types of cells and organisms. However, the shape of an organelle is typically described as part of its overall function or structure, rather than being a distinct concept with its own definition.
For example, mitochondria are often described as having a distinctive "fried egg" shape, with a round or oval outer membrane surrounding a more irregular inner membrane. Similarly, chloroplasts in plant cells have a characteristic disk or sac-like shape and contain stacks of flattened sacs called thylakoids.
In summary, while organelle shape is an important aspect of cell biology, it does not have a specific medical definition.
The Golgi apparatus, also known as the Golgi complex or simply the Golgi, is a membrane-bound organelle found in the cytoplasm of most eukaryotic cells. It plays a crucial role in the processing, sorting, and packaging of proteins and lipids for transport to their final destinations within the cell or for secretion outside the cell.
The Golgi apparatus consists of a series of flattened, disc-shaped sacs called cisternae, which are stacked together in a parallel arrangement. These stacks are often interconnected by tubular structures called tubules or vesicles. The Golgi apparatus has two main faces: the cis face, which is closest to the endoplasmic reticulum (ER) and receives proteins and lipids directly from the ER; and the trans face, which is responsible for sorting and dispatching these molecules to their final destinations.
The Golgi apparatus performs several essential functions in the cell:
1. Protein processing: After proteins are synthesized in the ER, they are transported to the cis face of the Golgi apparatus, where they undergo various post-translational modifications, such as glycosylation (the addition of sugar molecules) and sulfation. These modifications help determine the protein's final structure, function, and targeting.
2. Lipid modification: The Golgi apparatus also modifies lipids by adding or removing different functional groups, which can influence their properties and localization within the cell.
3. Protein sorting and packaging: Once proteins and lipids have been processed, they are sorted and packaged into vesicles at the trans face of the Golgi apparatus. These vesicles then transport their cargo to various destinations, such as lysosomes, plasma membrane, or extracellular space.
4. Intracellular transport: The Golgi apparatus serves as a central hub for intracellular trafficking, coordinating the movement of vesicles and other transport carriers between different organelles and cellular compartments.
5. Cell-cell communication: Some proteins that are processed and packaged in the Golgi apparatus are destined for secretion, playing crucial roles in cell-cell communication and maintaining tissue homeostasis.
In summary, the Golgi apparatus is a vital organelle involved in various cellular processes, including post-translational modification, sorting, packaging, and intracellular transport of proteins and lipids. Its proper functioning is essential for maintaining cellular homeostasis and overall organismal health.
Melanosomes are membrane-bound organelles found in melanocytes, the pigment-producing cells in the skin, hair, and eyes. They contain the pigment melanin, which is responsible for giving color to these tissues. Melanosomes are produced in the melanocyte and then transferred to surrounding keratinocytes in the epidermis via a process called cytocrinesis. There are four stages of melanosome development: stage I (immature), stage II (developing), stage III (mature), and stage IV (degrading). The amount and type of melanin in the melanosomes determine the color of an individual's skin, hair, and eyes. Mutations in genes involved in melanosome biogenesis or function can lead to various pigmentation disorders, such as albinism.
The endoplasmic reticulum (ER) is a network of interconnected tubules and sacs that are present in the cytoplasm of eukaryotic cells. It is a continuous membranous organelle that plays a crucial role in the synthesis, folding, modification, and transport of proteins and lipids.
The ER has two main types: rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER). RER is covered with ribosomes, which give it a rough appearance, and is responsible for protein synthesis. On the other hand, SER lacks ribosomes and is involved in lipid synthesis, drug detoxification, calcium homeostasis, and steroid hormone production.
In summary, the endoplasmic reticulum is a vital organelle that functions in various cellular processes, including protein and lipid metabolism, calcium regulation, and detoxification.
Autophagy is a fundamental cellular process that involves the degradation and recycling of damaged or unnecessary cellular components, such as proteins and organelles. The term "autophagy" comes from the Greek words "auto" meaning self and "phagy" meaning eating. It is a natural process that occurs in all types of cells and helps maintain cellular homeostasis by breaking down and recycling these components.
There are several different types of autophagy, including macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA). Macroautophagy is the most well-known form and involves the formation of a double-membraned vesicle called an autophagosome, which engulfs the cellular component to be degraded. The autophagosome then fuses with a lysosome, an organelle containing enzymes that break down and recycle the contents of the autophagosome.
Autophagy plays important roles in various cellular processes, including adaptation to starvation, removal of damaged organelles, clearance of protein aggregates, and regulation of programmed cell death (apoptosis). Dysregulation of autophagy has been implicated in a number of diseases, including cancer, neurodegenerative disorders, and infectious diseases.
Vacuoles are membrane-bound organelles found in the cells of most eukaryotic organisms. They are essentially fluid-filled sacs that store various substances, such as enzymes, waste products, and nutrients. In plants, vacuoles often contain water, ions, and various organic compounds, while in fungi, they may store lipids or pigments. Vacuoles can also play a role in maintaining the turgor pressure of cells, which is critical for cell shape and function.
In animal cells, vacuoles are typically smaller and less numerous than in plant cells. Animal cells have lysosomes, which are membrane-bound organelles that contain digestive enzymes and break down waste materials, cellular debris, and foreign substances. Lysosomes can be considered a type of vacuole, but they are more specialized in their function.
Overall, vacuoles are essential for maintaining the health and functioning of cells by providing a means to store and dispose of various substances.
Protein transport, in the context of cellular biology, refers to the process by which proteins are actively moved from one location to another within or between cells. This is a crucial mechanism for maintaining proper cell function and regulation.
Intracellular protein transport involves the movement of proteins within a single cell. Proteins can be transported across membranes (such as the nuclear envelope, endoplasmic reticulum, Golgi apparatus, or plasma membrane) via specialized transport systems like vesicles and transport channels.
Intercellular protein transport refers to the movement of proteins from one cell to another, often facilitated by exocytosis (release of proteins in vesicles) and endocytosis (uptake of extracellular substances via membrane-bound vesicles). This is essential for communication between cells, immune response, and other physiological processes.
It's important to note that any disruption in protein transport can lead to various diseases, including neurological disorders, cancer, and metabolic conditions.
Intracellular membranes refer to the membrane structures that exist within a eukaryotic cell (excluding bacteria and archaea, which are prokaryotic and do not have intracellular membranes). These membranes compartmentalize the cell, creating distinct organelles or functional regions with specific roles in various cellular processes.
Major types of intracellular membranes include:
1. Nuclear membrane (nuclear envelope): A double-membraned structure that surrounds and protects the genetic material within the nucleus. It consists of an outer and inner membrane, perforated by nuclear pores that regulate the transport of molecules between the nucleus and cytoplasm.
2. Endoplasmic reticulum (ER): An extensive network of interconnected tubules and sacs that serve as a major site for protein folding, modification, and lipid synthesis. The ER has two types: rough ER (with ribosomes on its surface) and smooth ER (without ribosomes).
3. Golgi apparatus/Golgi complex: A series of stacked membrane-bound compartments that process, sort, and modify proteins and lipids before they are transported to their final destinations within the cell or secreted out of the cell.
4. Lysosomes: Membrane-bound organelles containing hydrolytic enzymes for breaking down various biomolecules (proteins, carbohydrates, lipids, and nucleic acids) in the process called autophagy or from outside the cell via endocytosis.
5. Peroxisomes: Single-membrane organelles involved in various metabolic processes, such as fatty acid oxidation and detoxification of harmful substances like hydrogen peroxide.
6. Vacuoles: Membrane-bound compartments that store and transport various molecules, including nutrients, waste products, and enzymes. Plant cells have a large central vacuole for maintaining turgor pressure and storing metabolites.
7. Mitochondria: Double-membraned organelles responsible for generating energy (ATP) through oxidative phosphorylation and other metabolic processes, such as the citric acid cycle and fatty acid synthesis.
8. Chloroplasts: Double-membraned organelles found in plant cells that convert light energy into chemical energy during photosynthesis, producing oxygen and organic compounds (glucose) from carbon dioxide and water.
9. Endoplasmic reticulum (ER): A network of interconnected membrane-bound tubules involved in protein folding, modification, and transport; it is divided into two types: rough ER (with ribosomes on the surface) and smooth ER (without ribosomes).
10. Nucleus: Double-membraned organelle containing genetic material (DNA) and associated proteins involved in replication, transcription, RNA processing, and DNA repair. The nuclear membrane separates the nucleoplasm from the cytoplasm and contains nuclear pores for transporting molecules between the two compartments.
Peroxisomes are membrane-bound subcellular organelles found in the cytoplasm of eukaryotic cells. They play a crucial role in various cellular processes, including the breakdown of fatty acids and the detoxification of harmful substances such as hydrogen peroxide (H2O2). Peroxisomes contain numerous enzymes, including catalase, which converts H2O2 into water and oxygen, thus preventing oxidative damage to cellular components. They also participate in the biosynthesis of ether phospholipids, a type of lipid essential for the structure and function of cell membranes. Additionally, peroxisomes are involved in the metabolism of reactive oxygen species (ROS) and contribute to the regulation of intracellular redox homeostasis. Dysfunction or impairment of peroxisome function has been linked to several diseases, including neurological disorders, developmental abnormalities, and metabolic conditions.
Microtubules are hollow, cylindrical structures composed of tubulin proteins in the cytoskeleton of eukaryotic cells. They play crucial roles in various cellular processes such as maintaining cell shape, intracellular transport, and cell division (mitosis and meiosis). Microtubules are dynamic, undergoing continuous assembly and disassembly, which allows them to rapidly reorganize in response to cellular needs. They also form part of important cellular structures like centrioles, basal bodies, and cilia/flagella.
Endosomes are membrane-bound compartments within eukaryotic cells that play a critical role in intracellular trafficking and sorting of various cargoes, including proteins and lipids. They are formed by the invagination of the plasma membrane during endocytosis, resulting in the internalization of extracellular material and cell surface receptors.
Endosomes can be classified into early endosomes, late endosomes, and recycling endosomes based on their morphology, molecular markers, and functional properties. Early endosomes are the initial sorting stations for internalized cargoes, where they undergo sorting and processing before being directed to their final destinations. Late endosomes are more acidic compartments that mature from early endosomes and are responsible for the transport of cargoes to lysosomes for degradation.
Recycling endosomes, on the other hand, are involved in the recycling of internalized cargoes back to the plasma membrane or to other cellular compartments. Endosomal sorting and trafficking are regulated by a complex network of molecular interactions involving various proteins, lipids, and intracellular signaling pathways.
Defects in endosomal function have been implicated in various human diseases, including neurodegenerative disorders, developmental abnormalities, and cancer. Therefore, understanding the mechanisms underlying endosomal trafficking and sorting is of great importance for developing therapeutic strategies to treat these conditions.
Biological transport refers to the movement of molecules, ions, or solutes across biological membranes or through cells in living organisms. This process is essential for maintaining homeostasis, regulating cellular functions, and enabling communication between cells. There are two main types of biological transport: passive transport and active transport.
Passive transport does not require the input of energy and includes:
1. Diffusion: The random movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.
2. Osmosis: The diffusion of solvent molecules (usually water) across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
3. Facilitated diffusion: The assisted passage of polar or charged substances through protein channels or carriers in the cell membrane, which increases the rate of diffusion without consuming energy.
Active transport requires the input of energy (in the form of ATP) and includes:
1. Primary active transport: The direct use of ATP to move molecules against their concentration gradient, often driven by specific transport proteins called pumps.
2. Secondary active transport: The coupling of the movement of one substance down its electrochemical gradient with the uphill transport of another substance, mediated by a shared transport protein. This process is also known as co-transport or counter-transport.
Cell fractionation is a laboratory technique used to separate different cellular components or organelles based on their size, density, and other physical properties. This process involves breaking open the cell (usually through homogenization), and then separating the various components using various methods such as centrifugation, filtration, and ultracentrifugation.
The resulting fractions can include the cytoplasm, mitochondria, nuclei, endoplasmic reticulum, Golgi apparatus, lysosomes, peroxisomes, and other organelles. Each fraction can then be analyzed separately to study the biochemical and functional properties of the individual components.
Cell fractionation is a valuable tool in cell biology research, allowing scientists to study the structure, function, and interactions of various cellular components in a more detailed and precise manner.
Plastids are membrane-bound organelles found in the cells of plants and algae. They are responsible for various cellular functions, including photosynthesis, storage of starch, lipids, and proteins, and the production of pigments that give plants their color. The most common types of plastids are chloroplasts (which contain chlorophyll and are involved in photosynthesis), chromoplasts (which contain pigments such as carotenoids and are responsible for the yellow, orange, and red colors of fruits and flowers), and leucoplasts (which do not contain pigments and serve mainly as storage organelles). Plastids have their own DNA and can replicate themselves within the cell.
Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:
1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction
Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:
1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.
Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).
Kinesin is not a medical term per se, but a term from the field of cellular biology. However, understanding how kinesins work is important in the context of medical and cellular research.
Kinesins are a family of motor proteins that play a crucial role in transporting various cargoes within cells, such as vesicles, organelles, and chromosomes. They move along microtubule filaments, using the energy derived from ATP hydrolysis to generate mechanical force and motion. This process is essential for several cellular functions, including intracellular transport, mitosis, and meiosis.
In a medical context, understanding kinesin function can provide insights into various diseases and conditions related to impaired intracellular transport, such as neurodegenerative disorders (e.g., Alzheimer's disease, Parkinson's disease, and Huntington's disease) and certain genetic disorders affecting motor neurons. Research on kinesins can potentially lead to the development of novel therapeutic strategies targeting these conditions.
Cytoplasm is the material within a eukaryotic cell (a cell with a true nucleus) that lies between the nuclear membrane and the cell membrane. It is composed of an aqueous solution called cytosol, in which various organelles such as mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles are suspended. Cytoplasm also contains a variety of dissolved nutrients, metabolites, ions, and enzymes that are involved in various cellular processes such as metabolism, signaling, and transport. It is where most of the cell's metabolic activities take place, and it plays a crucial role in maintaining the structure and function of the cell.
Cytoplasmic granules are small, membrane-bound organelles or inclusions found within the cytoplasm of cells. They contain various substances such as proteins, lipids, carbohydrates, and genetic material. Cytoplasmic granules have diverse functions depending on their specific composition and cellular location. Some examples include:
1. Secretory granules: These are found in secretory cells and store hormones, neurotransmitters, or enzymes before they are released by exocytosis.
2. Lysosomes: These are membrane-bound organelles that contain hydrolytic enzymes for intracellular digestion of waste materials, foreign substances, and damaged organelles.
3. Melanosomes: Found in melanocytes, these granules produce and store the pigment melanin, which is responsible for skin, hair, and eye color.
4. Weibel-Palade bodies: These are found in endothelial cells and store von Willebrand factor and P-selectin, which play roles in hemostasis and inflammation.
5. Peroxisomes: These are single-membrane organelles that contain enzymes for various metabolic processes, such as β-oxidation of fatty acids and detoxification of harmful substances.
6. Lipid bodies (also called lipid droplets): These are cytoplasmic granules that store neutral lipids, such as triglycerides and cholesteryl esters. They play a role in energy metabolism and intracellular signaling.
7. Glycogen granules: These are cytoplasmic inclusions that store glycogen, a polysaccharide used for energy storage in animals.
8. Protein bodies: Found in plants, these granules store excess proteins and help regulate protein homeostasis within the cell.
9. Electron-dense granules: These are found in certain immune cells, such as mast cells and basophils, and release mediators like histamine during an allergic response.
10. Granules of unknown composition or function may also be present in various cell types.
Subcellular fractions refer to the separation and collection of specific parts or components of a cell, including organelles, membranes, and other structures, through various laboratory techniques such as centrifugation and ultracentrifugation. These fractions can be used in further biochemical and molecular analyses to study the structure, function, and interactions of individual cellular components. Examples of subcellular fractions include nuclear extracts, mitochondrial fractions, microsomal fractions (membrane vesicles), and cytosolic fractions (cytoplasmic extracts).
Fluorescence microscopy is a type of microscopy that uses fluorescent dyes or proteins to highlight and visualize specific components within a sample. In this technique, the sample is illuminated with high-energy light, typically ultraviolet (UV) or blue light, which excites the fluorescent molecules causing them to emit lower-energy, longer-wavelength light, usually visible light in the form of various colors. This emitted light is then collected by the microscope and detected to produce an image.
Fluorescence microscopy has several advantages over traditional brightfield microscopy, including the ability to visualize specific structures or molecules within a complex sample, increased sensitivity, and the potential for quantitative analysis. It is widely used in various fields of biology and medicine, such as cell biology, neuroscience, and pathology, to study the structure, function, and interactions of cells and proteins.
There are several types of fluorescence microscopy techniques, including widefield fluorescence microscopy, confocal microscopy, two-photon microscopy, and total internal reflection fluorescence (TIRF) microscopy, each with its own strengths and limitations. These techniques can provide valuable insights into the behavior of cells and proteins in health and disease.
A phagosome is a type of membrane-bound organelle that forms around a particle or microorganism following its engulfment by a cell, through the process of phagocytosis. This results in the formation of a vesicle containing the ingested material, which then fuses with another organelle called a lysosome to form a phago-lysosome. The lysosome contains enzymes that digest and break down the contents of the phagosome, allowing the cell to neutralize and dispose of potentially harmful substances or pathogens.
In summary, phagosomes are important organelles involved in the immune response, helping to protect the body against infection and disease.
Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.
Chloroplasts are specialized organelles found in the cells of green plants, algae, and some protists. They are responsible for carrying out photosynthesis, which is the process by which these organisms convert light energy from the sun into chemical energy in the form of organic compounds, such as glucose.
Chloroplasts contain the pigment chlorophyll, which absorbs light energy from the sun. They also contain a system of membranes and enzymes that convert carbon dioxide and water into glucose and oxygen through a series of chemical reactions known as the Calvin cycle. This process not only provides energy for the organism but also releases oxygen as a byproduct, which is essential for the survival of most life forms on Earth.
Chloroplasts are believed to have originated from ancient cyanobacteria that were engulfed by early eukaryotic cells and eventually became integrated into their host's cellular machinery through a process called endosymbiosis. Over time, chloroplasts evolved to become an essential component of plant and algal cells, contributing to their ability to carry out photosynthesis and thrive in a wide range of environments.
Cell compartmentation, also known as intracellular compartmentalization, refers to the organization of cells into distinct functional and spatial domains. This is achieved through the separation of cellular components and biochemical reactions into membrane-bound organelles or compartments. Each compartment has its unique chemical composition and environment, allowing for specific biochemical reactions to occur efficiently and effectively without interfering with other processes in the cell.
Some examples of membrane-bound organelles include the nucleus, mitochondria, chloroplasts, endoplasmic reticulum, Golgi apparatus, lysosomes, peroxisomes, and vacuoles. These organelles have specific functions, such as energy production (mitochondria), protein synthesis and folding (endoplasmic reticulum and Golgi apparatus), waste management (lysosomes), and lipid metabolism (peroxisomes).
Cell compartmentation is essential for maintaining cellular homeostasis, regulating metabolic pathways, protecting the cell from potentially harmful substances, and enabling complex biochemical reactions to occur in a controlled manner. Dysfunction of cell compartmentation can lead to various diseases, including neurodegenerative disorders, cancer, and metabolic disorders.
Cytoplasmic vesicles are membrane-bound sacs or compartments within the cytoplasm of a cell. They are formed by the pinching off of a portion of the cell membrane (a process called budding) or by the breakdown of larger organelles within the cell. These vesicles can contain various substances, such as proteins, lipids, carbohydrates, and enzymes, and they play a crucial role in many cellular processes, including intracellular transport, membrane trafficking, and waste disposal.
There are several types of cytoplasmic vesicles, including:
1. Endosomes: Vesicles that form when endocytic vesicles fuse with early endosomes, which then mature into late endosomes. These vesicles are involved in the transport and degradation of extracellular molecules that have been taken up by the cell through endocytosis.
2. Lysosomes: Membrane-bound organelles that contain hydrolytic enzymes for breaking down and recycling various biomolecules, such as proteins, carbohydrates, and lipids.
3. Transport vesicles: Small, membrane-bound sacs that transport proteins and other molecules between different cellular compartments. These vesicles can be classified based on their function, such as COPI (coat protein complex I) vesicles, which are involved in retrograde transport from the Golgi apparatus to the endoplasmic reticulum, or COPII (coat protein complex II) vesicles, which are involved in anterograde transport from the endoplasmic reticulum to the Golgi apparatus.
4. Secretory vesicles: Membrane-bound sacs that store proteins and other molecules destined for secretion from the cell. These vesicles fuse with the plasma membrane, releasing their contents into the extracellular space through a process called exocytosis.
5. Autophagosomes: Double-membraned vesicles that form around cytoplasmic components during the process of autophagy, a cellular mechanism for degrading and recycling damaged organelles and protein aggregates. The autophagosome fuses with a lysosome, forming an autolysosome, where the contents are broken down and recycled.
6. Peroxisomes: Membrane-bound organelles that contain enzymes for oxidizing and detoxifying various molecules, such as fatty acids and amino acids. They also play a role in the synthesis of bile acids and plasmalogens, a type of lipid found in cell membranes.
7. Lysosomes: Membrane-bound organelles that contain hydrolytic enzymes for breaking down various biomolecules, such as proteins, carbohydrates, and lipids. They are involved in the degradation of materials delivered to them through endocytosis, phagocytosis, or autophagy.
8. Endosomes: Membrane-bound organelles that form during the process of endocytosis, where extracellular material is internalized into the cell. Early endosomes are involved in sorting and trafficking of internalized molecules, while late endosomes are acidic compartments that mature into lysosomes for degradation of their contents.
9. Golgi apparatus: Membrane-bound organelles that function as a central hub for the processing, modification, and sorting of proteins and lipids. They receive newly synthesized proteins from the endoplasmic reticulum and modify them through various enzymatic reactions before packaging them into vesicles for transport to their final destinations.
10. Endoplasmic reticulum (ER): Membrane-bound organelles that function as a site for protein synthesis, folding, and modification. The ER is continuous with the nuclear membrane and consists of two distinct domains: the rough ER, which contains ribosomes on its surface for protein synthesis, and the smooth ER, which lacks ribosomes and functions in lipid metabolism and detoxification of xenobiotics.
11. Mitochondria: Membrane-bound organelles that function as the powerhouse of the cell, generating ATP through oxidative phosphorylation. They contain their own DNA and are believed to have originated from free-living bacteria that were engulfed by a eukaryotic host cell in an ancient endosymbiotic event.
12. Nucleus: Membrane-bound organelle that contains the genetic material of the cell, including DNA and histone proteins. The nucleus is surrounded by a double membrane called the nuclear envelope, which is perforated by nuclear pores that allow for the selective transport of molecules between the nucleus and the cytoplasm.
13. Cytoskeleton: A network of protein filaments that provide structural support and organization to the cell. The cytoskeleton consists of three main types of filaments: microtubules, intermediate filaments, and actin filaments, which differ in their composition, structure, and function.
14. Plasma membrane: Membrane-bound organelle that surrounds the cell and separates it from its external environment. The plasma membrane is composed of a phospholipid bilayer with embedded proteins and carbohydrate chains, and functions as a selective barrier that regulates the exchange of molecules between the cell and its surroundings.
15. Endoplasmic reticulum (ER): Membrane-bound organelle that consists of an interconnected network of tubules and sacs that extend throughout the cytoplasm. The ER is involved in various cellular processes, including protein synthesis, lipid metabolism, and calcium homeostasis.
16. Golgi apparatus: Membrane-bound organelle that consists of a series of flattened sacs called cisternae, which are arranged in a stack-like structure. The Golgi apparatus is involved in the modification and sorting of proteins and lipids, and plays a key role in the formation of lysosomes, secretory vesicles, and the plasma membrane.
17. Lysosomes: Membrane-bound organelles that contain hydrolytic enzymes that can break down various biomolecules, including proteins, carbohydrates, lipids, and nucleic acids. Lysosomes are involved in the degradation of cellular waste, damaged organelles, and foreign particles, and play a crucial role in the maintenance of cellular homeostasis.
18. Peroxisomes: Membrane-bound organelles that contain various enzymes that are involved in oxidative metabolism, including the breakdown of fatty acids and the detoxification of harmful substances. Peroxisomes also play a role in the biosynthesis of certain lipids and hormones.
19. Mitochondria: Membrane-bound organelles that are involved in energy production, metabolism, and signaling. Mitochondria contain their own DNA and are believed to have originated from ancient bacteria that were engulfed by eukaryotic cells. They consist of an outer membrane, an inner membrane, and a matrix, and are involved in various cellular processes, including oxidative phosphorylation, the citric acid cycle, and the regulation of calcium homeostasis.
20. Nucleus: Membrane-bound organelle that contains the genetic material of the cell, including DNA and histone proteins. The nucleus is involved in various cellular processes, including gene expression, DNA replication, and RNA processing. It is surrounded by a double membrane called the nuclear envelope, which is pierced by numerous pores that allow for the exchange of molecules between the nucleus and the cytoplasm.
21. Endoplasmic reticulum (ER): Membranous network that is involved in protein synthesis, folding, and modification. The ER consists of a system of interconnected tubules and sacs that are continuous with the nuclear envelope. It is divided into two main regions: the rough ER, which is studded with ribosomes and is involved in protein synthesis, and the smooth ER, which lacks ribosomes and is involved in lipid metabolism and detoxification.
22. Golgi apparatus: Membranous organelle that is involved in the sorting, modification, and transport of proteins and lipids. The Golgi apparatus consists of a stack of flattened sacs called cisternae, which are surrounded by vesicles and tubules. It receives proteins and lipids from the ER and modifies them by adding sugar molecules or other modifications before sending them to their final destinations.
23. Lysosomes: Membrane-bound organelles that contain hydrolytic enzymes that break down and recycle cellular waste and foreign materials. Lysosomes are formed by the fusion of vesicles derived
Cytoplasmic streaming, also known as cyclosis, is the movement or flow of cytoplasm and organelles within a eukaryotic cell. It is a type of intracellular transport that occurs in many types of cells, but it is particularly prominent in large, single-celled organisms such as algae and fungi.
During cytoplasmic streaming, the cytoplasm moves in a coordinated and organized manner, often in circular or spiral patterns. This movement is driven by the action of motor proteins, such as myosin, which interact with filamentous structures called actin filaments. The movement of the motor proteins along the actin filaments generates force, causing the cytoplasm and organelles to move.
Cytoplasmic streaming serves several functions in cells. It helps to distribute nutrients and metabolic products throughout the cell, and it also plays a role in the movement of organelles and other cellular components to specific locations within the cell. Additionally, cytoplasmic streaming can help to maintain the structural integrity of large, single-celled organisms by ensuring that their cytoplasm is evenly distributed.
Cilia are tiny, hair-like structures that protrude from the surface of many types of cells in the body. They are composed of a core bundle of microtubules surrounded by a protein matrix and are covered with a membrane. Cilia are involved in various cellular functions, including movement of fluid or mucus across the cell surface, detection of external stimuli, and regulation of signaling pathways.
There are two types of cilia: motile and non-motile. Motile cilia are able to move in a coordinated manner to propel fluids or particles across a surface, such as those found in the respiratory tract and reproductive organs. Non-motile cilia, also known as primary cilia, are present on most cells in the body and serve as sensory organelles that detect chemical and mechanical signals from the environment.
Defects in cilia structure or function can lead to a variety of diseases, collectively known as ciliopathies. These conditions can affect multiple organs and systems in the body, including the brain, kidneys, liver, and eyes. Examples of ciliopathies include polycystic kidney disease, Bardet-Biedl syndrome, and Meckel-Gruber syndrome.
A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.
Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.
Examples of biological models include:
1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.
Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.
Axonal transport is the controlled movement of materials and organelles within axons, which are the nerve fibers of neurons (nerve cells). This intracellular transport system is essential for maintaining the structural and functional integrity of axons, particularly in neurons with long axonal processes. There are two types of axonal transport: anterograde transport, which moves materials from the cell body toward the synaptic terminals, and retrograde transport, which transports materials from the synaptic terminals back to the cell body. Anterograde transport is typically slower than retrograde transport and can be divided into fast and slow components based on velocity. Fast anterograde transport moves vesicles containing neurotransmitters and their receptors, as well as mitochondria and other organelles, at speeds of up to 400 mm/day. Slow anterograde transport moves cytoskeletal elements, proteins, and RNA at speeds of 1-10 mm/day. Retrograde transport is primarily responsible for recycling membrane components, removing damaged organelles, and transmitting signals from the axon terminal to the cell body. Dysfunctions in axonal transport have been implicated in various neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS).
Melanophores are specialized pigment-containing cells found in various organisms, including vertebrates and some invertebrates. In humans and other mammals, melanophores are primarily located within the skin's dermal layer and are part of the larger group of chromatophores.
Melanophores contain melanosomes, which are organelles that store and transport the pigment melanin. These cells play a crucial role in determining the coloration of an individual's skin, hair, and eyes by producing, storing, and distributing melanin granules within their cytoplasm.
In response to hormonal signals or neural stimulation, melanophores can undergo changes in the distribution of melanosomes, leading to variations in color intensity. This process is known as melanin dispersion or aggregation and is responsible for various physiological responses, such as skin tanning upon exposure to sunlight or the color-changing abilities observed in some animals like chameleons and cuttlefish.
It's important to note that while humans do not have the ability to change their skin color rapidly like some other animals, melanophores still play a significant role in protecting our skin from harmful ultraviolet radiation by producing melanin, which helps absorb and dissipate this energy, reducing damage to skin cells.
Immunoelectron microscopy (IEM) is a specialized type of electron microscopy that combines the principles of immunochemistry and electron microscopy to detect and localize specific antigens within cells or tissues at the ultrastructural level. This technique allows for the visualization and identification of specific proteins, viruses, or other antigenic structures with a high degree of resolution and specificity.
In IEM, samples are first fixed, embedded, and sectioned to prepare them for electron microscopy. The sections are then treated with specific antibodies that have been labeled with electron-dense markers, such as gold particles or ferritin. These labeled antibodies bind to the target antigens in the sample, allowing for their visualization under an electron microscope.
There are several different methods of IEM, including pre-embedding and post-embedding techniques. Pre-embedding involves labeling the antigens before embedding the sample in resin, while post-embedding involves labeling the antigens after embedding. Post-embedding techniques are generally more commonly used because they allow for better preservation of ultrastructure and higher resolution.
IEM is a valuable tool in many areas of research, including virology, bacteriology, immunology, and cell biology. It can be used to study the structure and function of viruses, bacteria, and other microorganisms, as well as the distribution and localization of specific proteins and antigens within cells and tissues.
Transmission electron microscopy (TEM) is a type of microscopy in which an electron beam is transmitted through a ultra-thin specimen, interacting with it as it passes through. An image is formed from the interaction of the electrons with the specimen; the image is then magnified and visualized on a fluorescent screen or recorded on an electronic detector (or photographic film in older models).
TEM can provide high-resolution, high-magnification images that can reveal the internal structure of specimens including cells, viruses, and even molecules. It is widely used in biological and materials science research to investigate the ultrastructure of cells, tissues and materials. In medicine, TEM is used for diagnostic purposes in fields such as virology and bacteriology.
It's important to note that preparing a sample for TEM is a complex process, requiring specialized techniques to create thin (50-100 nm) specimens. These include cutting ultrathin sections of embedded samples using an ultramicrotome, staining with heavy metal salts, and positive staining or negative staining methods.
Rab GTP-binding proteins, also known as Rab GTPases or simply Rabs, are a large family of small GTP-binding proteins that play a crucial role in regulating intracellular vesicle trafficking. They function as molecular switches that cycle between an active GTP-bound state and an inactive GDP-bound state.
In the active state, Rab proteins interact with various effector molecules to mediate specific membrane trafficking events such as vesicle budding, transport, tethering, and fusion. Each Rab protein is thought to have a unique function and localize to specific intracellular compartments or membranes, where they regulate the transport of vesicles and organelles within the cell.
Rab proteins are involved in several important cellular processes, including endocytosis, exocytosis, Golgi apparatus function, autophagy, and intracellular signaling. Dysregulation of Rab GTP-binding proteins has been implicated in various human diseases, such as cancer, neurodegenerative disorders, and infectious diseases.
An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.
Endocytosis is the process by which cells absorb substances from their external environment by engulfing them in membrane-bound structures, resulting in the formation of intracellular vesicles. This mechanism allows cells to take up large molecules, such as proteins and lipids, as well as small particles, like bacteria and viruses. There are two main types of endocytosis: phagocytosis (cell eating) and pinocytosis (cell drinking). Phagocytosis involves the engulfment of solid particles, while pinocytosis deals with the uptake of fluids and dissolved substances. Other specialized forms of endocytosis include receptor-mediated endocytosis and caveolae-mediated endocytosis, which allow for the specific internalization of molecules through the interaction with cell surface receptors.
Medical Definition:
Microtubule-associated proteins (MAPs) are a diverse group of proteins that bind to microtubules, which are key components of the cytoskeleton in eukaryotic cells. MAPs play crucial roles in regulating microtubule dynamics and stability, as well as in mediating interactions between microtubules and other cellular structures. They can be classified into several categories based on their functions, including:
1. Microtubule stabilizers: These MAPs promote the assembly of microtubules and protect them from disassembly by enhancing their stability. Examples include tau proteins and MAP2.
2. Microtubule dynamics regulators: These MAPs modulate the rate of microtubule polymerization and depolymerization, allowing for dynamic reorganization of the cytoskeleton during cell division and other processes. Examples include stathmin and XMAP215.
3. Microtubule motor proteins: These MAPs use energy from ATP hydrolysis to move along microtubules, transporting various cargoes within the cell. Examples include kinesin and dynein.
4. Adapter proteins: These MAPs facilitate interactions between microtubules and other cellular structures, such as membranes, organelles, or signaling molecules. Examples include MAP4 and CLASPs.
Dysregulation of MAPs has been implicated in several diseases, including neurodegenerative disorders like Alzheimer's disease (where tau proteins form abnormal aggregates called neurofibrillary tangles) and cancer (where altered microtubule dynamics can contribute to uncontrolled cell division).
Dyneins are a type of motor protein that play an essential role in the movement of cellular components and structures within eukaryotic cells. They are responsible for generating force and motion along microtubules, which are critical components of the cell's cytoskeleton. Dyneins are involved in various cellular processes, including intracellular transport, organelle positioning, and cell division.
There are several types of dyneins, but the two main categories are cytoplasmic dyneins and axonemal dyneins. Cytoplasmic dyneins are responsible for moving various cargoes, such as vesicles, organelles, and mRNA complexes, toward the minus-end of microtubules, which is usually located near the cell center. Axonemal dyneins, on the other hand, are found in cilia and flagella and are responsible for their movement by sliding adjacent microtubules past each other.
Dyneins consist of multiple subunits, including heavy chains, intermediate chains, light-intermediate chains, and light chains. The heavy chains contain the motor domain that binds to microtubules and hydrolyzes ATP to generate force. Dysfunction in dynein proteins has been linked to various human diseases, such as neurodevelopmental disorders, ciliopathies, and cancer.
Transport vesicles are membrane-bound sacs or containers within cells that are responsible for the intracellular transport of proteins, lipids, and other cargo. These vesicles form when a portion of a donor membrane buds off, enclosing the cargo inside. There are different types of transport vesicles, including:
1. Endoplasmic reticulum (ER) vesicles: These vesicles form from the ER and transport proteins to the Golgi apparatus for further processing.
2. Golgi-derived vesicles: After proteins have been processed in the Golgi, they are packaged into transport vesicles that can deliver them to their final destinations within the cell or to the plasma membrane for secretion.
3. Endocytic vesicles: These vesicles form when a portion of the plasma membrane invaginates and pinches off, engulfing extracellular material or fluid. Examples include clathrin-coated vesicles and caveolae.
4. Lysosomal vesicles: These vesicles transport materials to lysosomes for degradation.
5. Secretory vesicles: These vesicles store proteins and other molecules that will be secreted from the cell. When stimulated, these vesicles fuse with the plasma membrane, releasing their contents to the extracellular space.
A genome is the complete set of genetic material present within an organism. In eukaryotic cells, which include plants, animals, and other complex life forms, the genome is divided into several compartments, including the nucleus (where most of the genetic material is housed) and the plastids (which include chloroplasts in plant cells).
A plastid genome, also known as a plastome, is the genetic material found within a plastid. Plastids are organelles found in the cells of plants, algae, and some protists that are involved in various metabolic processes, including photosynthesis. The plastid genome is typically a circular molecule of DNA that contains genes encoding for proteins, ribosomal RNA (rRNA), and transfer RNA (tRNA) that are necessary for the function and maintenance of the plastid.
The plastid genome is relatively small compared to the nuclear genome, typically ranging from 120-160 kilobases in length. The gene content and organization of plastid genomes are highly conserved across different plant species, making them useful tools for studying evolutionary relationships among plants. Additionally, because plastids are maternally inherited in many plant species, the plastid genome has been used to study patterns of maternal inheritance and hybridization in plants.
Green Fluorescent Protein (GFP) is not a medical term per se, but a scientific term used in the field of molecular biology. GFP is a protein that exhibits bright green fluorescence when exposed to light, particularly blue or ultraviolet light. It was originally discovered in the jellyfish Aequorea victoria.
In medical and biological research, scientists often use recombinant DNA technology to introduce the gene for GFP into other organisms, including bacteria, plants, and animals, including humans. This allows them to track the expression and localization of specific genes or proteins of interest in living cells, tissues, or even whole organisms.
The ability to visualize specific cellular structures or processes in real-time has proven invaluable for a wide range of research areas, from studying the development and function of organs and organ systems to understanding the mechanisms of diseases and the effects of therapeutic interventions.
The cell nucleus is a membrane-bound organelle found in the eukaryotic cells (cells with a true nucleus). It contains most of the cell's genetic material, organized as DNA molecules in complex with proteins, RNA molecules, and histones to form chromosomes.
The primary function of the cell nucleus is to regulate and control the activities of the cell, including growth, metabolism, protein synthesis, and reproduction. It also plays a crucial role in the process of mitosis (cell division) by separating and protecting the genetic material during this process. The nuclear membrane, or nuclear envelope, surrounding the nucleus is composed of two lipid bilayers with numerous pores that allow for the selective transport of molecules between the nucleoplasm (nucleus interior) and the cytoplasm (cell exterior).
The cell nucleus is a vital structure in eukaryotic cells, and its dysfunction can lead to various diseases, including cancer and genetic disorders.
Microbodies are small, membrane-bound organelles found in the cells of eukaryotic organisms. They typically measure between 0.2 to 0.5 micrometers in diameter and play a crucial role in various metabolic processes, particularly in the detoxification of harmful substances and the synthesis of lipids.
There are several types of microbodies, including:
1. Peroxisomes: These are the most common type of microbody. They contain enzymes that help break down fatty acids and amino acids, producing hydrogen peroxide as a byproduct. Another set of enzymes within peroxisomes then converts the harmful hydrogen peroxide into water and oxygen, thus detoxifying the cell.
2. Glyoxysomes: These microbodies are primarily found in plants and some fungi. They contain enzymes involved in the glyoxylate cycle, a metabolic pathway that helps convert stored fats into carbohydrates during germination.
3. Microbody-like particles (MLPs): These are smaller organelles found in certain protists and algae. Their functions are not well understood but are believed to be involved in lipid metabolism.
It is important to note that microbodies do not have a uniform structure or function across all eukaryotic cells, and their specific roles can vary depending on the organism and cell type.
Mitochondrial proteins are any proteins that are encoded by the nuclear genome or mitochondrial genome and are located within the mitochondria, an organelle found in eukaryotic cells. These proteins play crucial roles in various cellular processes including energy production, metabolism of lipids, amino acids, and steroids, regulation of calcium homeostasis, and programmed cell death or apoptosis.
Mitochondrial proteins can be classified into two main categories based on their origin:
1. Nuclear-encoded mitochondrial proteins (NEMPs): These are proteins that are encoded by genes located in the nucleus, synthesized in the cytoplasm, and then imported into the mitochondria through specific import pathways. NEMPs make up about 99% of all mitochondrial proteins and are involved in various functions such as oxidative phosphorylation, tricarboxylic acid (TCA) cycle, fatty acid oxidation, and mitochondrial dynamics.
2. Mitochondrial DNA-encoded proteins (MEPs): These are proteins that are encoded by the mitochondrial genome, synthesized within the mitochondria, and play essential roles in the electron transport chain (ETC), a key component of oxidative phosphorylation. The human mitochondrial genome encodes only 13 proteins, all of which are subunits of complexes I, III, IV, and V of the ETC.
Defects in mitochondrial proteins can lead to various mitochondrial disorders, which often manifest as neurological, muscular, or metabolic symptoms due to impaired energy production. These disorders are usually caused by mutations in either nuclear or mitochondrial genes that encode mitochondrial proteins.
Eukaryotic cells are complex cells that characterize the cells of all living organisms except bacteria and archaea. They are typically larger than prokaryotic cells and contain a true nucleus and other membrane-bound organelles. The nucleus houses the genetic material, DNA, which is organized into chromosomes. Other organelles include mitochondria, responsible for energy production; chloroplasts, present in plant cells and responsible for photosynthesis; endoplasmic reticulum, involved in protein synthesis; Golgi apparatus, involved in the processing and transport of proteins and lipids; lysosomes, involved in digestion and waste disposal; and vacuoles, involved in storage and waste management. Eukaryotic cells also have a cytoskeleton made up of microtubules, intermediate filaments, and actin filaments that provide structure, support, and mobility to the cell.
Myosin Type V is an molecular motor protein involved in the intracellular transport of various cargoes, including vesicles and organelles. It belongs to the family of myosins, which are actin-based motors that convert chemical energy into mechanical work through the hydrolysis of ATP.
Myosin V is characterized by its long tail domain, which allows it to form dimers or higher-order oligomers, and its head domain, which binds to actin filaments and hydrolyzes ATP to generate force and movement. The protein moves in a hand-over-hand manner along the actin filament, allowing it to transport cargoes over long distances within the cell.
Myosin V has been implicated in various cellular processes, including exocytosis, endocytosis, and organelle positioning. Mutations in the MYO5A gene, which encodes Myosin Type V, have been associated with several human genetic disorders, such as Griscelli syndrome type 1 and familial progressive arthro-ophthalmopathy.
I'm sorry for any confusion, but "Protozoan Proteins" is not a specific medical or scientific term. Protozoa are single-celled eukaryotic organisms, and proteins are large biological molecules consisting of one or more chains of amino acid residues. Therefore, "Protozoan Proteins" generally refers to the various types of proteins found in protozoa.
However, if you're looking for information about proteins specific to certain protozoan parasites with medical relevance (such as Plasmodium falciparum, which causes malaria), I would be happy to help! Please provide more context or specify the particular protozoan of interest.
Confocal microscopy is a powerful imaging technique used in medical and biological research to obtain high-resolution, contrast-rich images of thick samples. This super-resolution technology provides detailed visualization of cellular structures and processes at various depths within a specimen.
In confocal microscopy, a laser beam focused through a pinhole illuminates a small spot within the sample. The emitted fluorescence or reflected light from this spot is then collected by a detector, passing through a second pinhole that ensures only light from the focal plane reaches the detector. This process eliminates out-of-focus light, resulting in sharp images with improved contrast compared to conventional widefield microscopy.
By scanning the laser beam across the sample in a raster pattern and collecting fluorescence at each point, confocal microscopy generates optical sections of the specimen. These sections can be combined to create three-dimensional reconstructions, allowing researchers to study cellular architecture and interactions within complex tissues.
Confocal microscopy has numerous applications in medical research, including studying protein localization, tracking intracellular dynamics, analyzing cell morphology, and investigating disease mechanisms at the cellular level. Additionally, it is widely used in clinical settings for diagnostic purposes, such as analyzing skin lesions or detecting pathogens in patient samples.
Eukaryota is a domain that consists of organisms whose cells have a true nucleus and complex organelles. This domain includes animals, plants, fungi, and protists. The term "eukaryote" comes from the Greek words "eu," meaning true or good, and "karyon," meaning nut or kernel. In eukaryotic cells, the genetic material is housed within a membrane-bound nucleus, and the DNA is organized into chromosomes. This is in contrast to prokaryotic cells, which do not have a true nucleus and have their genetic material dispersed throughout the cytoplasm.
Eukaryotic cells are generally larger and more complex than prokaryotic cells. They have many different organelles, including mitochondria, chloroplasts, endoplasmic reticulum, and Golgi apparatus, that perform specific functions to support the cell's metabolism and survival. Eukaryotic cells also have a cytoskeleton made up of microtubules, actin filaments, and intermediate filaments, which provide structure and shape to the cell and allow for movement of organelles and other cellular components.
Eukaryotes are diverse and can be found in many different environments, ranging from single-celled organisms that live in water or soil to multicellular organisms that live on land or in aquatic habitats. Some eukaryotes are unicellular, meaning they consist of a single cell, while others are multicellular, meaning they consist of many cells that work together to form tissues and organs.
In summary, Eukaryota is a domain of organisms whose cells have a true nucleus and complex organelles. This domain includes animals, plants, fungi, and protists, and the eukaryotic cells are generally larger and more complex than prokaryotic cells.
A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.
Secretory vesicles are membrane-bound organelles found within cells that store and transport secretory proteins and other molecules to the plasma membrane for exocytosis. Exocytosis is the process by which these molecules are released from the cell, allowing them to perform various functions, such as communication with other cells or participation in biochemical reactions. Secretory vesicles can be found in a variety of cell types, including endocrine cells, exocrine cells, and neurons. The proteins and molecules contained within secretory vesicles are synthesized in the rough endoplasmic reticulum and then transported to the Golgi apparatus, where they are processed, modified, and packaged into the vesicles for subsequent release.
"Saccharomyces cerevisiae" is not typically considered a medical term, but it is a scientific name used in the field of microbiology. It refers to a species of yeast that is commonly used in various industrial processes, such as baking and brewing. It's also widely used in scientific research due to its genetic tractability and eukaryotic cellular organization.
However, it does have some relevance to medical fields like medicine and nutrition. For example, certain strains of S. cerevisiae are used as probiotics, which can provide health benefits when consumed. They may help support gut health, enhance the immune system, and even assist in the digestion of certain nutrients.
In summary, "Saccharomyces cerevisiae" is a species of yeast with various industrial and potential medical applications.
Vacuolar Proton-Translocating ATPases (V-ATPases) are complex enzyme systems that are found in the membranes of various intracellular organelles, such as vacuoles, endosomes, lysosomes, and Golgi apparatus. They play a crucial role in the establishment and maintenance of electrochemical gradients across these membranes by actively pumping protons (H+) from the cytosol to the lumen of the organelles.
The V-ATPases are composed of two major components: a catalytic domain, known as V1, which contains multiple subunits and is responsible for ATP hydrolysis; and a membrane-bound domain, called V0, which consists of several subunits and facilitates proton translocation. The energy generated from ATP hydrolysis in the V1 domain is used to drive conformational changes in the V0 domain, resulting in the vectorial transport of protons across the membrane.
These electrochemical gradients established by V-ATPases are essential for various cellular processes, including secondary active transport, maintenance of organellar pH, protein sorting and trafficking, and regulation of cell volume. Dysfunction in V-ATPases has been implicated in several human diseases, such as neurodegenerative disorders, renal tubular acidosis, and certain types of cancer.
The cytoskeleton is a complex network of various protein filaments that provides structural support, shape, and stability to the cell. It plays a crucial role in maintaining cellular integrity, intracellular organization, and enabling cell movement. The cytoskeleton is composed of three major types of protein fibers: microfilaments (actin filaments), intermediate filaments, and microtubules. These filaments work together to provide mechanical support, participate in cell division, intracellular transport, and help maintain the cell's architecture. The dynamic nature of the cytoskeleton allows cells to adapt to changing environmental conditions and respond to various stimuli.
Cytosol refers to the liquid portion of the cytoplasm found within a eukaryotic cell, excluding the organelles and structures suspended in it. It is the site of various metabolic activities and contains a variety of ions, small molecules, and enzymes. The cytosol is where many biochemical reactions take place, including glycolysis, protein synthesis, and the regulation of cellular pH. It is also where some organelles, such as ribosomes and vesicles, are located. In contrast to the cytosol, the term "cytoplasm" refers to the entire contents of a cell, including both the cytosol and the organelles suspended within it.
Molecular motor proteins are a type of protein that convert chemical energy into mechanical work at the molecular level. They play a crucial role in various cellular processes, such as cell division, muscle contraction, and intracellular transport. There are several types of molecular motor proteins, including myosin, kinesin, and dynein.
Myosin is responsible for muscle contraction and movement along actin filaments in the cytoplasm. Kinesin and dynein are involved in intracellular transport along microtubules, moving cargo such as vesicles, organelles, and mRNA to various destinations within the cell.
These motor proteins move in a stepwise fashion, with each step driven by the hydrolysis of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate (Pi). The directionality and speed of movement are determined by the structure and regulation of the motor proteins, as well as the properties of the tracks along which they move.
Luminescent proteins are a type of protein that emit light through a chemical reaction, rather than by absorbing and re-emitting light like fluorescent proteins. This process is called bioluminescence. The light emitted by luminescent proteins is often used in scientific research as a way to visualize and track biological processes within cells and organisms.
One of the most well-known luminescent proteins is Green Fluorescent Protein (GFP), which was originally isolated from jellyfish. However, GFP is actually a fluorescent protein, not a luminescent one. A true example of a luminescent protein is the enzyme luciferase, which is found in fireflies and other bioluminescent organisms. When luciferase reacts with its substrate, luciferin, it produces light through a process called oxidation.
Luminescent proteins have many applications in research, including as reporters for gene expression, as markers for protein-protein interactions, and as tools for studying the dynamics of cellular processes. They are also used in medical imaging and diagnostics, as well as in the development of new therapies.
Vesicular transport proteins are specialized proteins that play a crucial role in the intracellular trafficking and transportation of various biomolecules, such as proteins and lipids, within eukaryotic cells. These proteins facilitate the formation, movement, and fusion of membrane-bound vesicles, which are small, spherical structures that carry cargo between different cellular compartments or organelles.
There are several types of vesicular transport proteins involved in this process:
1. Coat Proteins (COPs): These proteins form a coat around the vesicle membrane and help shape it into its spherical form during the budding process. They also participate in selecting and sorting cargo for transportation. Two main types of COPs exist: COPI, which is involved in transport between the Golgi apparatus and the endoplasmic reticulum (ER), and COPII, which mediates transport from the ER to the Golgi apparatus.
2. SNARE Proteins: These proteins are responsible for the specific recognition and docking of vesicles with their target membranes. They form complexes that bring the vesicle and target membranes close together, allowing for fusion and the release of cargo into the target organelle. There are two types of SNARE proteins: v-SNAREs (vesicle SNAREs) and t-SNAREs (target SNAREs), which interact to form a stable complex during membrane fusion.
3. Rab GTPases: These proteins act as molecular switches that regulate the recruitment of coat proteins, motor proteins, and SNAREs during vesicle transport. They cycle between an active GTP-bound state and an inactive GDP-bound state, controlling the various stages of vesicular trafficking, such as budding, transport, tethering, and fusion.
4. Tethering Proteins: These proteins help to bridge the gap between vesicles and their target membranes before SNARE-mediated fusion occurs. They play a role in ensuring specificity during vesicle docking and may also contribute to regulating the timing of membrane fusion events.
5. Soluble N-ethylmaleimide-sensitive factor Attachment Protein Receptors (SNAREs): These proteins are involved in intracellular transport, particularly in the trafficking of vesicles between organelles. They consist of a family of coiled-coil domain-containing proteins that form complexes to mediate membrane fusion events.
Overall, these various classes of proteins work together to ensure the specificity and efficiency of vesicular transport in eukaryotic cells. Dysregulation or mutation of these proteins can lead to various diseases, including neurodegenerative disorders and cancer.
Flagella are long, thin, whip-like structures that some types of cells use to move themselves around. They are made up of a protein called tubulin and are surrounded by a membrane. In bacteria, flagella rotate like a propeller to push the cell through its environment. In eukaryotic cells (cells with a true nucleus), such as sperm cells or certain types of algae, flagella move in a wave-like motion to achieve locomotion. The ability to produce flagella is called flagellation.
"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.
Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.
It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.
Recombinant fusion proteins are artificially created biomolecules that combine the functional domains or properties of two or more different proteins into a single protein entity. They are generated through recombinant DNA technology, where the genes encoding the desired protein domains are linked together and expressed as a single, chimeric gene in a host organism, such as bacteria, yeast, or mammalian cells.
The resulting fusion protein retains the functional properties of its individual constituent proteins, allowing for novel applications in research, diagnostics, and therapeutics. For instance, recombinant fusion proteins can be designed to enhance protein stability, solubility, or immunogenicity, making them valuable tools for studying protein-protein interactions, developing targeted therapies, or generating vaccines against infectious diseases or cancer.
Examples of recombinant fusion proteins include:
1. Etaglunatide (ABT-523): A soluble Fc fusion protein that combines the heavy chain fragment crystallizable region (Fc) of an immunoglobulin with the extracellular domain of the human interleukin-6 receptor (IL-6R). This fusion protein functions as a decoy receptor, neutralizing IL-6 and its downstream signaling pathways in rheumatoid arthritis.
2. Etanercept (Enbrel): A soluble TNF receptor p75 Fc fusion protein that binds to tumor necrosis factor-alpha (TNF-α) and inhibits its proinflammatory activity, making it a valuable therapeutic option for treating autoimmune diseases like rheumatoid arthritis, ankylosing spondylitis, and psoriasis.
3. Abatacept (Orencia): A fusion protein consisting of the extracellular domain of cytotoxic T-lymphocyte antigen 4 (CTLA-4) linked to the Fc region of an immunoglobulin, which downregulates T-cell activation and proliferation in autoimmune diseases like rheumatoid arthritis.
4. Belimumab (Benlysta): A monoclonal antibody that targets B-lymphocyte stimulator (BLyS) protein, preventing its interaction with the B-cell surface receptor and inhibiting B-cell activation in systemic lupus erythematosus (SLE).
5. Romiplostim (Nplate): A fusion protein consisting of a thrombopoietin receptor agonist peptide linked to an immunoglobulin Fc region, which stimulates platelet production in patients with chronic immune thrombocytopenia (ITP).
6. Darbepoetin alfa (Aranesp): A hyperglycosylated erythropoiesis-stimulating protein that functions as a longer-acting form of recombinant human erythropoietin, used to treat anemia in patients with chronic kidney disease or cancer.
7. Palivizumab (Synagis): A monoclonal antibody directed against the F protein of respiratory syncytial virus (RSV), which prevents RSV infection and is administered prophylactically to high-risk infants during the RSV season.
8. Ranibizumab (Lucentis): A recombinant humanized monoclonal antibody fragment that binds and inhibits vascular endothelial growth factor A (VEGF-A), used in the treatment of age-related macular degeneration, diabetic retinopathy, and other ocular disorders.
9. Cetuximab (Erbitux): A chimeric monoclonal antibody that binds to epidermal growth factor receptor (EGFR), used in the treatment of colorectal cancer and head and neck squamous cell carcinoma.
10. Adalimumab (Humira): A fully humanized monoclonal antibody that targets tumor necrosis factor-alpha (TNF-α), used in the treatment of various inflammatory diseases, including rheumatoid arthritis, psoriasis, and Crohn's disease.
11. Bevacizumab (Avastin): A recombinant humanized monoclonal antibody that binds to VEGF-A, used in the treatment of various cancers, including colorectal, lung, breast, and kidney cancer.
12. Trastuzumab (Herceptin): A humanized monoclonal antibody that targets HER2/neu receptor, used in the treatment of breast cancer.
13. Rituximab (Rituxan): A chimeric monoclonal antibody that binds to CD20 antigen on B cells, used in the treatment of non-Hodgkin's lymphoma and rheumatoid arthritis.
14. Palivizumab (Synagis): A humanized monoclonal antibody that binds to the F protein of respiratory syncytial virus, used in the prevention of respiratory syncytial virus infection in high-risk infants.
15. Infliximab (Remicade): A chimeric monoclonal antibody that targets TNF-α, used in the treatment of various inflammatory diseases, including Crohn's disease, ulcerative colitis, rheumatoid arthritis, and ankylosing spondylitis.
16. Natalizumab (Tysabri): A humanized monoclonal antibody that binds to α4β1 integrin, used in the treatment of multiple sclerosis and Crohn's disease.
17. Adalimumab (Humira): A fully human monoclonal antibody that targets TNF-α, used in the treatment of various inflammatory diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, and ulcerative colitis.
18. Golimumab (Simponi): A fully human monoclonal antibody that targets TNF-α, used in the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis.
19. Certolizumab pegol (Cimzia): A PEGylated Fab' fragment of a humanized monoclonal antibody that targets TNF-α, used in the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and Crohn's disease.
20. Ustekinumab (Stelara): A fully human monoclonal antibody that targets IL-12 and IL-23, used in the treatment of psoriasis, psoriatic arthritis, and Crohn's disease.
21. Secukinumab (Cosentyx): A fully human monoclonal antibody that targets IL-17A, used in the treatment of psoriasis, psoriatic arthritis, and ankylosing spondylitis.
22. Ixekizumab (Taltz): A fully human monoclonal antibody that targets IL-17A, used in the treatment of psoriasis and psoriatic arthritis.
23. Brodalumab (Siliq): A fully human monoclonal antibody that targets IL-17 receptor A, used in the treatment of psoriasis.
24. Sarilumab (Kevzara): A fully human monoclonal antibody that targets the IL-6 receptor, used in the treatment of rheumatoid arthritis.
25. Tocilizumab (Actemra): A humanized monoclonal antibody that targets the IL-6 receptor, used in the treatment of rheumatoid arthritis, systemic juvenile idiopathic arthritis, polyarticular juvenile idiopathic arthritis, giant cell arteritis, and chimeric antigen receptor T-cell-induced cytokine release syndrome.
26. Siltuximab (Sylvant): A chimeric monoclonal antibody that targets IL-6, used in the treatment of multicentric Castleman disease.
27. Satralizumab (Enspryng): A humanized monoclonal antibody that targets IL-6 receptor alpha, used in the treatment of neuromyelitis optica spectrum disorder.
28. Sirukumab (Plivensia): A human monoclonal antibody that targets IL-6, used in the treatment
Chlorophyta is a division of green algae, also known as green plants. This group includes a wide variety of simple, aquatic organisms that contain chlorophylls a and b, which gives them their characteristic green color. They are a diverse group, ranging from unicellular forms to complex multicellular seaweeds. Chlorophyta is a large and varied division with approximately 7,00
Mitochondrial membranes refer to the double-layered structure that surrounds the mitochondrion, an organelle found in the cells of most eukaryotes. The outer mitochondrial membrane is a smooth, porous membrane that allows small molecules and ions to pass through freely, while the inner mitochondrial membrane is highly folded and selectively permeable, controlling the movement of larger molecules and maintaining the electrochemical gradient necessary for ATP synthesis. The space between the two membranes is called the intermembrane space, and the space within the inner membrane is called the matrix. Together, these membranes play a crucial role in energy production, metabolism, and cellular homeostasis.
'Cellular structures' is a broad term that refers to the various components and organizations of cells in living organisms. In a medical context, it can refer to the study of cellular morphology and organization in various tissues and organs, as well as changes in these structures that may be associated with disease or injury.
Cellular structures can include:
1. Cell membrane: The outer boundary of the cell that separates it from the extracellular environment and regulates the movement of molecules into and out of the cell.
2. Cytoplasm: The contents of the cell, including organelles such as mitochondria, ribosomes, endoplasmic reticulum, and Golgi apparatus.
3. Nucleus: The central organelle that contains the genetic material (DNA) of the cell and controls its activities.
4. Mitochondria: Organelles that generate energy for the cell through a process called cellular respiration.
5. Endoplasmic reticulum (ER): A network of tubules and sacs that serve as a site for protein synthesis, folding, and modification.
6. Golgi apparatus: A membrane-bound organelle that modifies, sorts, and packages proteins and lipids for transport to other parts of the cell or for secretion from the cell.
7. Lysosomes: Organelles that contain enzymes that break down waste materials and cellular debris.
8. Cytoskeleton: A network of protein filaments that provide structure, shape, and movement to the cell.
9. Ribosomes: Organelles that synthesize proteins using instructions from the DNA in the nucleus.
Abnormalities in these cellular structures can be associated with various medical conditions, such as cancer, genetic disorders, infectious diseases, and neurodegenerative disorders.
A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.
Lysosome-Associated Membrane Glycoproteins (LAMPs) are a group of proteins found in the membrane of lysosomes, which are cellular organelles responsible for breaking down and recycling various biomolecules. LAMPs play a crucial role in maintaining the integrity and function of the lysosomal membrane.
There are two major types of LAMPs: LAMP-1 and LAMP-2. Both proteins share structural similarities, including a large heavily glycosylated domain that faces the lumen of the lysosome and a short hydrophobic region that anchors them to the membrane.
The primary function of LAMPs is to protect the lysosomal membrane from degradation by hydrolytic enzymes present inside the lysosome. They also participate in the process of autophagy, a cellular recycling mechanism, by fusing with autophagosomes (double-membraned vesicles formed during autophagy) to form autolysosomes, where the contents are degraded.
Moreover, LAMPs have been implicated in several cellular processes, such as antigen presentation, cholesterol homeostasis, and intracellular signaling. Mutations in LAMP-2 have been associated with certain genetic disorders, including Danon disease, a rare X-linked dominant disorder characterized by heart problems, muscle weakness, and intellectual disability.
A Blastocystis is a single-celled microscopic organism (protozoan) that can inhabit the human gastrointestinal tract. It is found in the stool of infected individuals and is classified as a stramenopile, which is a group of organisms that also includes algae and water molds.
Blastocystis is often considered a commensal organism, meaning that it can live in the human gut without causing any harm. However, some studies have suggested that Blastocystis may be associated with gastrointestinal symptoms such as diarrhea, abdominal pain, and bloating, particularly in people with compromised immune systems or other underlying health conditions.
There is ongoing debate among researchers about the role of Blastocystis in human health, and more research is needed to fully understand its impact on the gut microbiome and overall health. Currently, there is no consensus on whether or not to treat Blastocystis in asymptomatic individuals.
Membrane fusion is a fundamental biological process that involves the merging of two initially separate lipid bilayers, such as those surrounding cells or organelles, to form a single continuous membrane. This process plays a crucial role in various physiological events including neurotransmitter release, hormone secretion, fertilization, viral infection, and intracellular trafficking of proteins and lipids. Membrane fusion is tightly regulated and requires the participation of specific proteins called SNAREs (Soluble NSF Attachment Protein REceptors) and other accessory factors that facilitate the recognition, approximation, and merger of the membranes. The energy required to overcome the repulsive forces between the negatively charged lipid headgroups is provided by these proteins, which undergo conformational changes during the fusion process. Membrane fusion is a highly specific and coordinated event, ensuring that the correct membranes fuse at the right time and place within the cell.
The secretory pathway is a series of membrane-enclosed compartments within eukaryotic cells that are involved in the synthesis, modification, and transport of proteins and lipids. The pathway begins in the endoplasmic reticulum (ER), where proteins and lipids are synthesized and folded.
Proteins that are destined for secretion or for incorporation into membranes are then transported from the ER to the Golgi apparatus, where they undergo further modifications such as glycosylation and sorting. After passing through the Golgi, proteins and lipids are sorted and packaged into vesicles that bud off from the Golgi and are transported to their final destinations, which may include the plasma membrane, lysosomes, or other organelles.
The secretory pathway is essential for many cellular processes, including the production and secretion of hormones, enzymes, and other proteins, as well as the maintenance of cell membranes and the regulation of intracellular signaling.
The Fluorescent Antibody Technique (FAT) is a type of immunofluorescence assay used in laboratory medicine and pathology for the detection and localization of specific antigens or antibodies in tissues, cells, or microorganisms. In this technique, a fluorescein-labeled antibody is used to selectively bind to the target antigen or antibody, forming an immune complex. When excited by light of a specific wavelength, the fluorescein label emits light at a longer wavelength, typically visualized as green fluorescence under a fluorescence microscope.
The FAT is widely used in diagnostic microbiology for the identification and characterization of various bacteria, viruses, fungi, and parasites. It has also been applied in the diagnosis of autoimmune diseases and certain cancers by detecting specific antibodies or antigens in patient samples. The main advantage of FAT is its high sensitivity and specificity, allowing for accurate detection and differentiation of various pathogens and disease markers. However, it requires specialized equipment and trained personnel to perform and interpret the results.
Mitochondrial dynamics refer to the processes that regulate the shape, size, distribution, and quality control of mitochondria within cells. These dynamic processes include:
1. Mitochondrial Fusion: This is the process by which two adjacent mitochondria merge together to form a single, elongated organelle. Fusion allows for the exchange of mitochondrial content, including DNA, proteins, and metabolites, which helps maintain genetic stability and promote bioenergetic efficiency.
2. Mitochondrial Fission: This is the process by which a single mitochondrion divides into two separate organelles. Fission plays a crucial role in mitochondrial division, inheritance, and quality control, as it enables the segregation of damaged or dysfunctional mitochondria for degradation via autophagy (mitophagy).
3. Mitochondrial Transport: This is the active movement of mitochondria within cells, facilitated by cytoskeletal motor proteins. Mitochondrial transport enables organelles to be distributed evenly throughout the cell and to reach specific subcellular locations where their energy demands are high.
4. Mitochondrial Dynamics Regulation: The regulation of mitochondrial dynamics involves a complex interplay between various proteins, lipids, and signaling pathways that control fusion, fission, transport, and quality control processes. These regulatory mechanisms help maintain the balance between mitochondrial biogenesis (the generation of new organelles) and mitophagy (the removal of damaged ones), ensuring proper cellular homeostasis and function.
Dysregulation of mitochondrial dynamics has been implicated in various pathological conditions, including neurodegenerative diseases, metabolic disorders, and aging-related processes.
A mitochondrial genome refers to the genetic material present in the mitochondria, which are small organelles found in the cytoplasm of eukaryotic cells (cells with a true nucleus). The mitochondrial genome is typically circular and contains a relatively small number of genes compared to the nuclear genome.
Mitochondrial DNA (mtDNA) encodes essential components of the electron transport chain, which is vital for cellular respiration and energy production. MtDNA also contains genes that code for some mitochondrial tRNAs and rRNAs needed for protein synthesis within the mitochondria.
In humans, the mitochondrial genome is about 16.6 kilobases in length and consists of 37 genes: 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 13 protein-coding genes. The mitochondrial genome is inherited maternally, as sperm contribute very few or no mitochondria during fertilization. Mutations in the mitochondrial genome can lead to various genetic disorders, often affecting tissues with high energy demands, such as muscle and nerve cells.
Carrier proteins, also known as transport proteins, are a type of protein that facilitates the movement of molecules across cell membranes. They are responsible for the selective and active transport of ions, sugars, amino acids, and other molecules from one side of the membrane to the other, against their concentration gradient. This process requires energy, usually in the form of ATP (adenosine triphosphate).
Carrier proteins have a specific binding site for the molecule they transport, and undergo conformational changes upon binding, which allows them to move the molecule across the membrane. Once the molecule has been transported, the carrier protein returns to its original conformation, ready to bind and transport another molecule.
Carrier proteins play a crucial role in maintaining the balance of ions and other molecules inside and outside of cells, and are essential for many physiological processes, including nerve impulse transmission, muscle contraction, and nutrient uptake.
Saccharomyces cerevisiae proteins are the proteins that are produced by the budding yeast, Saccharomyces cerevisiae. This organism is a single-celled eukaryote that has been widely used as a model organism in scientific research for many years due to its relatively simple genetic makeup and its similarity to higher eukaryotic cells.
The genome of Saccharomyces cerevisiae has been fully sequenced, and it is estimated to contain approximately 6,000 genes that encode proteins. These proteins play a wide variety of roles in the cell, including catalyzing metabolic reactions, regulating gene expression, maintaining the structure of the cell, and responding to environmental stimuli.
Many Saccharomyces cerevisiae proteins have human homologs and are involved in similar biological processes, making this organism a valuable tool for studying human disease. For example, many of the proteins involved in DNA replication, repair, and recombination in yeast have human counterparts that are associated with cancer and other diseases. By studying these proteins in yeast, researchers can gain insights into their function and regulation in humans, which may lead to new treatments for disease.
Brefeldin A is a fungal metabolite that inhibits protein transport from the endoplasmic reticulum to the Golgi apparatus. It disrupts the organization of the Golgi complex and causes the redistribution of its proteins to the endoplasmic reticulum. Brefeldin A is used in research to study various cellular processes, including vesicular transport, protein trafficking, and signal transduction pathways. In medicine, it has been studied as a potential anticancer agent due to its ability to induce apoptosis (programmed cell death) in certain types of cancer cells. However, its clinical use is not yet approved.
Inclusion bodies are abnormal, intracellular accumulations or aggregations of various misfolded proteins, protein complexes, or other materials within the cells of an organism. They can be found in various tissues and cell types and are often associated with several pathological conditions, including infectious diseases, neurodegenerative disorders, and genetic diseases.
Inclusion bodies can vary in size, shape, and location depending on the specific disease or condition. Some inclusion bodies have a characteristic appearance under the microscope, such as eosinophilic (pink) staining with hematoxylin and eosin (H&E) histological stain, while others may require specialized stains or immunohistochemical techniques to identify the specific misfolded proteins involved.
Examples of diseases associated with inclusion bodies include:
1. Infectious diseases: Some viral infections, such as HIV, hepatitis B and C, and herpes simplex virus, can lead to the formation of inclusion bodies within infected cells.
2. Neurodegenerative disorders: Several neurodegenerative diseases are characterized by the presence of inclusion bodies, including Alzheimer's disease (amyloid-beta plaques and tau tangles), Parkinson's disease (Lewy bodies), Huntington's disease (Huntingtin aggregates), and amyotrophic lateral sclerosis (TDP-43 and SOD1 inclusions).
3. Genetic diseases: Certain genetic disorders, such as Danon disease, neuronal intranuclear inclusion disease, and some lysosomal storage disorders, can also present with inclusion bodies due to the accumulation of abnormal proteins or metabolic products within cells.
The exact role of inclusion bodies in disease pathogenesis remains unclear; however, they are often associated with cellular dysfunction, oxidative stress, and increased inflammation, which can contribute to disease progression and neurodegeneration.
Mitochondrial DNA (mtDNA) is the genetic material present in the mitochondria, which are specialized structures within cells that generate energy. Unlike nuclear DNA, which is present in the cell nucleus and inherited from both parents, mtDNA is inherited solely from the mother.
MtDNA is a circular molecule that contains 37 genes, including 13 genes that encode for proteins involved in oxidative phosphorylation, a process that generates energy in the form of ATP. The remaining genes encode for rRNAs and tRNAs, which are necessary for protein synthesis within the mitochondria.
Mutations in mtDNA can lead to a variety of genetic disorders, including mitochondrial diseases, which can affect any organ system in the body. These mutations can also be used in forensic science to identify individuals and establish biological relationships.
Weibel-Palade bodies are rod-shaped, membrane-bound organelles found in the cytoplasm of endothelial cells, which line the interior surface of blood vessels. They were first described by Edwin Weibel and George Palade in 1964. These organelles are unique to endothelial cells and serve as storage sites for von Willebrand factor (vWF) and other proteins involved in hemostasis, inflammation, and vasomotor functions.
The main components of Weibel-Palade bodies include:
1. Von Willebrand factor (vWF): A multimeric glycoprotein that plays a crucial role in platelet adhesion and aggregation at the site of vascular injury, as well as mediating the transport of coagulation factors VIII and V.
2. P-selectin: A cell adhesion molecule that facilitates leukocyte rolling and recruitment to sites of inflammation.
3. Endothelial nitric oxide synthase (eNOS): An enzyme responsible for the production of nitric oxide, a potent vasodilator that regulates vascular tone and blood flow.
4. Angiopoietin-2: A growth factor involved in angiogenesis and vascular remodeling.
5. Tissue plasminogen activator (tPA): A serine protease that plays a role in fibrinolysis, the process of breaking down blood clots.
Upon stimulation by various agonists such as thrombin, histamine, or vascular endothelial growth factor (VEGF), Weibel-Palade bodies undergo exocytosis, releasing their contents into the extracellular space. This process contributes to hemostatic responses, inflammatory reactions, and modulation of vascular tone.
Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:
Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.
Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.
Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.
'Arabidopsis' is a genus of small flowering plants that are part of the mustard family (Brassicaceae). The most commonly studied species within this genus is 'Arabidopsis thaliana', which is often used as a model organism in plant biology and genetics research. This plant is native to Eurasia and Africa, and it has a small genome that has been fully sequenced. It is known for its short life cycle, self-fertilization, and ease of growth, making it an ideal subject for studying various aspects of plant biology, including development, metabolism, and response to environmental stresses.
Adaptor Protein Complex 3 (APC3), also known as AP-3, is a type of adaptor protein complex that plays a crucial role in the sorting and trafficking of proteins within cells. It is composed of four subunits: delta, beta3A, mu3, and sigma3A. APC3 is primarily involved in the transport of proteins from the early endosomes to the lysosomes or to the plasma membrane. It also plays a role in the biogenesis of lysosome-related organelles such as melanosomes and platelet-dense granules. Mutations in the genes encoding for APC3 subunits have been associated with several genetic disorders, including Hermansky-Pudlak syndrome and Chediak-Higashi syndrome.
I apologize for any confusion, but "plants" is not a term that has a medical definition. The term "plants" refers to a large and diverse group of organisms that obtain their energy through photosynthesis, which is the process of converting sunlight into chemical energy. Plants are typically characterized by having cells with cell walls containing cellulose, chloroplasts containing the pigment chlorophyll, and the ability to synthesize their own food through photosynthesis.
In a medical or biological context, you might be thinking of "plant-based" or "phytomedicine," which refer to the use of plants or plant extracts as a form of medicine or treatment. Phytomedicines have been used for thousands of years in many traditional systems of medicine, and some plant-derived compounds have been found to have therapeutic benefits in modern medicine as well. However, "plants" itself does not have a medical definition.
The smooth endoplasmic reticulum (SER) is a type of organelle in the cell that is involved in various metabolic processes. It is called "smooth" because it lacks ribosomes on its surface, which gives it a smooth appearance compared to the rough endoplasmic reticulum (RER), which has ribosomes attached to it.
The main function of the SER is to synthesize lipids, including cholesterol and phospholipids, which are essential components of cell membranes. It also plays a role in the metabolism of carbohydrates, steroids, and drugs. In addition, the SER is involved in calcium homeostasis, as it contains a large amount of calcium ions that can be released into the cytoplasm when needed.
The SER is found throughout the cell but is particularly abundant in cells that synthesize and secrete large amounts of lipids, such as liver cells, steroid-producing cells, and adipose tissue cells. It is also found in high concentrations in cells that are involved in detoxification, such as those in the liver and kidney.
Centrifugation, Density Gradient is a medical laboratory technique used to separate and purify different components of a mixture based on their size, density, and shape. This method involves the use of a centrifuge and a density gradient medium, such as sucrose or cesium chloride, to create a stable density gradient within a column or tube.
The sample is carefully layered onto the top of the gradient and then subjected to high-speed centrifugation. During centrifugation, the particles in the sample move through the gradient based on their size, density, and shape, with heavier particles migrating faster and further than lighter ones. This results in the separation of different components of the mixture into distinct bands or zones within the gradient.
This technique is commonly used to purify and concentrate various types of biological materials, such as viruses, organelles, ribosomes, and subcellular fractions, from complex mixtures. It allows for the isolation of pure and intact particles, which can then be collected and analyzed for further study or use in downstream applications.
In summary, Centrifugation, Density Gradient is a medical laboratory technique used to separate and purify different components of a mixture based on their size, density, and shape using a centrifuge and a density gradient medium.
Cell biology is the branch of biology that deals with the study of cells, which are the basic units of life. It involves understanding the structure, function, and behavior of cells, as well as their interactions with one another and with their environment. Cell biologists may study various aspects of cellular processes, such as cell growth and division, metabolism, gene expression, signal transduction, and intracellular transport. They use a variety of techniques, including microscopy, biochemistry, genetics, and molecular biology, to investigate the complex and dynamic world inside cells. The ultimate goal of cell biology is to gain a deeper understanding of how cells work, which can have important implications for human health and disease.
Adenosine Triphosphate (ATP) is a high-energy molecule that stores and transports energy within cells. It is the main source of energy for most cellular processes, including muscle contraction, nerve impulse transmission, and protein synthesis. ATP is composed of a base (adenine), a sugar (ribose), and three phosphate groups. The bonds between these phosphate groups contain a significant amount of energy, which can be released when the bond between the second and third phosphate group is broken, resulting in the formation of adenosine diphosphate (ADP) and inorganic phosphate. This process is known as hydrolysis and can be catalyzed by various enzymes to drive a wide range of cellular functions. ATP can also be regenerated from ADP through various metabolic pathways, such as oxidative phosphorylation or substrate-level phosphorylation, allowing for the continuous supply of energy to cells.
Exocytosis is the process by which cells release molecules, such as hormones or neurotransmitters, to the extracellular space. This process involves the transport of these molecules inside vesicles (membrane-bound sacs) to the cell membrane, where they fuse and release their contents to the outside of the cell. It is a crucial mechanism for intercellular communication and the regulation of various physiological processes in the body.
An axon is a long, slender extension of a neuron (a type of nerve cell) that conducts electrical impulses (nerve impulses) away from the cell body to target cells, such as other neurons or muscle cells. Axons can vary in length from a few micrometers to over a meter long and are typically surrounded by a myelin sheath, which helps to insulate and protect the axon and allows for faster transmission of nerve impulses.
Axons play a critical role in the functioning of the nervous system, as they provide the means by which neurons communicate with one another and with other cells in the body. Damage to axons can result in serious neurological problems, such as those seen in spinal cord injuries or neurodegenerative diseases like multiple sclerosis.
Proteins are complex, large molecules that play critical roles in the body's functions. They are made up of amino acids, which are organic compounds that are the building blocks of proteins. Proteins are required for the structure, function, and regulation of the body's tissues and organs. They are essential for the growth, repair, and maintenance of body tissues, and they play a crucial role in many biological processes, including metabolism, immune response, and cellular signaling. Proteins can be classified into different types based on their structure and function, such as enzymes, hormones, antibodies, and structural proteins. They are found in various foods, especially animal-derived products like meat, dairy, and eggs, as well as plant-based sources like beans, nuts, and grains.
The actin cytoskeleton is a complex, dynamic network of filamentous (threadlike) proteins that provides structural support and shape to cells, allows for cell movement and division, and plays a role in intracellular transport. Actin filaments are composed of actin monomers that polymerize to form long, thin fibers. These filaments can be organized into different structures, such as stress fibers, which provide tension and support, or lamellipodia and filopodia, which are involved in cell motility. The actin cytoskeleton is constantly remodeling in response to various intracellular and extracellular signals, allowing for changes in cell shape and behavior.
I'm sorry for any confusion, but "magnetosomes" is not a term commonly used in medical terminology. It is a term that is more frequently used in the field of biology and geobiology to refer to membrane-enclosed magnetic nanocrystals found in certain types of bacteria. These magnetosomes are used by the bacteria for magnetotaxis, or orientation based on the Earth's magnetic field. If you have any questions about a medical term or concept, I would be happy to help answer those!
HeLa cells are a type of immortalized cell line used in scientific research. They are derived from a cancer that developed in the cervical tissue of Henrietta Lacks, an African-American woman, in 1951. After her death, cells taken from her tumor were found to be capable of continuous division and growth in a laboratory setting, making them an invaluable resource for medical research.
HeLa cells have been used in a wide range of scientific studies, including research on cancer, viruses, genetics, and drug development. They were the first human cell line to be successfully cloned and are able to grow rapidly in culture, doubling their population every 20-24 hours. This has made them an essential tool for many areas of biomedical research.
It is important to note that while HeLa cells have been instrumental in numerous scientific breakthroughs, the story of their origin raises ethical questions about informed consent and the use of human tissue in research.
Fluorescent dyes are substances that emit light upon excitation by absorbing light of a shorter wavelength. In a medical context, these dyes are often used in various diagnostic tests and procedures to highlight or mark certain structures or substances within the body. For example, fluorescent dyes may be used in imaging techniques such as fluorescence microscopy or fluorescence angiography to help visualize cells, tissues, or blood vessels. These dyes can also be used in flow cytometry to identify and sort specific types of cells. The choice of fluorescent dye depends on the specific application and the desired properties, such as excitation and emission spectra, quantum yield, and photostability.
Hydrogen-ion concentration, also known as pH, is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (to the base 10) of the hydrogen ion activity in a solution. The standard unit of measurement is the pH unit. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.
In medical terms, hydrogen-ion concentration is important for maintaining homeostasis within the body. For example, in the stomach, a high hydrogen-ion concentration (low pH) is necessary for the digestion of food. However, in other parts of the body such as blood, a high hydrogen-ion concentration can be harmful and lead to acidosis. Conversely, a low hydrogen-ion concentration (high pH) in the blood can lead to alkalosis. Both acidosis and alkalosis can have serious consequences on various organ systems if not corrected.
"Plant proteins" refer to the proteins that are derived from plant sources. These can include proteins from legumes such as beans, lentils, and peas, as well as proteins from grains like wheat, rice, and corn. Other sources of plant proteins include nuts, seeds, and vegetables.
Plant proteins are made up of individual amino acids, which are the building blocks of protein. While animal-based proteins typically contain all of the essential amino acids that the body needs to function properly, many plant-based proteins may be lacking in one or more of these essential amino acids. However, by consuming a variety of plant-based foods throughout the day, it is possible to get all of the essential amino acids that the body needs from plant sources alone.
Plant proteins are often lower in calories and saturated fat than animal proteins, making them a popular choice for those following a vegetarian or vegan diet, as well as those looking to maintain a healthy weight or reduce their risk of chronic diseases such as heart disease and cancer. Additionally, plant proteins have been shown to have a number of health benefits, including improving gut health, reducing inflammation, and supporting muscle growth and repair.
Histochemistry is the branch of pathology that deals with the microscopic localization of cellular or tissue components using specific chemical reactions. It involves the application of chemical techniques to identify and locate specific biomolecules within tissues, cells, and subcellular structures. This is achieved through the use of various staining methods that react with specific antigens or enzymes in the sample, allowing for their visualization under a microscope. Histochemistry is widely used in diagnostic pathology to identify different types of tissues, cells, and structures, as well as in research to study cellular and molecular processes in health and disease.
Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.
In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.
Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.
Actin is a type of protein that forms part of the contractile apparatus in muscle cells, and is also found in various other cell types. It is a globular protein that polymerizes to form long filaments, which are important for many cellular processes such as cell division, cell motility, and the maintenance of cell shape. In muscle cells, actin filaments interact with another type of protein called myosin to enable muscle contraction. Actins can be further divided into different subtypes, including alpha-actin, beta-actin, and gamma-actin, which have distinct functions and expression patterns in the body.
Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.
Decapodiformes is a taxonomic order of marine cephalopods, which includes squids, octopuses, and cuttlefish. The name "Decapodiformes" comes from the Greek words "deca," meaning ten, and "podos," meaning foot, referring to the fact that these animals have ten limbs.
However, it is worth noting that within Decapodiformes, octopuses are an exception as they only have eight arms. The other members of this order, such as squids and cuttlefish, have ten appendages, which are used for locomotion, feeding, and sensory perception.
Decapodiformes species are known for their complex behaviors, sophisticated communication systems, and remarkable adaptations that enable them to thrive in a variety of marine habitats. They play important ecological roles as both predators and prey in the ocean food chain.
Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.
Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.
The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.
Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.
The trans-Golgi network (TGN) is a structure in the cell's endomembrane system that is involved in the sorting and distribution of proteins and lipids to their final destinations within the cell or for secretion. It is a part of the Golgi apparatus, which consists of a series of flattened, membrane-bound sacs called cisternae. The TGN is located at the trans face (or "exit" side) of the Golgi complex and is the final stop for proteins that have been modified as they pass through the Golgi stacks.
At the TGN, proteins are sorted into different transport vesicles based on their specific targeting signals. These vesicles then bud off from the TGN and move to their respective destinations, such as endosomes, lysosomes, the plasma membrane, or secretory vesicles for exocytosis. The TGN also plays a role in the modification of lipids and the formation of primary lysosomes.
In summary, the trans-Golgi network is a crucial sorting and distribution center within the cell that ensures proteins and lipids reach their correct destinations to maintain proper cellular function.
Electron microscope tomography (EMT) is a 3D imaging technique used in electron microscopy. It involves collecting a series of images of a sample at different tilt angles, and then using computational algorithms to reconstruct the 3D structure of the sample from these images.
In EMT, a sample is prepared and placed in an electron microscope, where it is exposed to a beam of electrons. The electrons interact with the atoms in the sample, producing contrast that allows the features of the sample to be visualized. By tilting the sample and collecting images at multiple angles, a range of perspectives can be obtained, which are then used to create a 3D reconstruction of the sample.
EMT is a powerful tool for studying the ultrastructure of cells and tissues, as it allows researchers to visualize structures that may not be visible using other imaging techniques. It has been used to study a wide range of biological systems, including viruses, bacteria, organelles, and cells.
EMT is a complex technique that requires specialized equipment and expertise to perform. However, it can provide valuable insights into the structure and function of biological systems, making it an important tool in the field of biology and medicine.
Centrioles are small, cylindrical structures found in the centrosome of animal cells. They play a crucial role in organizing the microtubules that make up the cell's cytoskeleton and are also involved in the formation of the spindle apparatus during cell division. A typical centriole is made up of nine sets of triplet microtubules arranged in a ring-like fashion around a central hub or core.
Centrioles have two main functions:
1. Microtubule Organization: Centrioles serve as the primary site for microtubule nucleation and organization within the cell. They help to form the mitotic spindle during cell division, which is responsible for separating replicated chromosomes into two identical sets that are distributed equally between the two daughter cells.
2. Formation of Cilia and Flagella: In specialized cells, centrioles can also function as basal bodies for the formation of cilia and flagella. These hair-like structures protrude from the cell surface and play a role in cell movement and the movement of extracellular fluids over the cell surface.
It is important to note that plants and fungi do not have centrioles, and their cells use alternative mechanisms for microtubule organization and cell division.
Apicomplexa is a phylum of single-celled, parasitic organisms that includes several medically important genera, such as Plasmodium (which causes malaria), Toxoplasma (which causes toxoplasmosis), and Cryptosporidium (which causes cryptosporidiosis). These organisms are characterized by the presence of a unique apical complex, which is a group of specialized structures at one end of the cell that are used during invasion and infection of host cells. They have a complex life cycle involving multiple stages, including sexual and asexual reproduction, often in different hosts. Many Apicomplexa are intracellular parasites, meaning they live and multiply inside the cells of their hosts.
Potassium iodide is an inorganic, non-radioactive salt of iodine. Medically, it is used as a thyroid blocking agent to prevent the absorption of radioactive iodine in the event of a nuclear accident or radiation exposure. It works by saturating the thyroid gland with stable iodide, which then prevents the uptake of radioactive iodine. This can help reduce the risk of thyroid cancer and other thyroid related issues that may arise from exposure to radioactive materials. Potassium iodide is also used in the treatment of iodine deficiency disorders.
"Toxoplasma" is a genus of protozoan parasites, and the most well-known species is "Toxoplasma gondii." This particular species is capable of infecting virtually all warm-blooded animals, including humans. It's known for its complex life cycle that involves felines (cats) as the definitive host.
Infection in humans, called toxoplasmosis, often occurs through ingestion of contaminated food or water, or through contact with cat feces that contain T. gondii oocysts. While many people infected with Toxoplasma show no symptoms, it can cause serious health problems in immunocompromised individuals and developing fetuses if a woman becomes infected during pregnancy.
It's important to note that while I strive to provide accurate information, this definition should not be used for self-diagnosis or treatment. Always consult with a healthcare professional for medical advice.
Propylene glycol is not a medical term, but rather a chemical compound. However, it does have various applications in the medical field. Medically, propylene glycol can be used as a:
1. Vehicle for intravenous (IV) medications: Propylene glycol helps dissolve drugs that are not water-soluble and allows them to be administered intravenously. It is used in the preparation of some IV medications, including certain antibiotics, antivirals, and chemotherapeutic agents.
2. Preservative: Propylene glycol acts as a preservative in various medical products, such as topical ointments, eye drops, and injectable solutions, to prevent bacterial growth and increase shelf life.
3. Humectant: In some medical devices and pharmaceutical formulations, propylene glycol is used as a humectant, which means it helps maintain moisture and prevent dryness in the skin or mucous membranes.
The chemical definition of propylene glycol (C3H8O2) is:
A colorless, nearly odorless, viscous liquid belonging to the alcohol family. It is a diol, meaning it contains two hydroxyl groups (-OH), and its molecular formula is C3H8O2. Propylene glycol is miscible with water and most organic solvents and has applications in various industries, including pharmaceuticals, food processing, cosmetics, and industrial manufacturing.
Lipid metabolism is the process by which the body breaks down and utilizes lipids (fats) for various functions, such as energy production, cell membrane formation, and hormone synthesis. This complex process involves several enzymes and pathways that regulate the digestion, absorption, transport, storage, and consumption of fats in the body.
The main types of lipids involved in metabolism include triglycerides, cholesterol, phospholipids, and fatty acids. The breakdown of these lipids begins in the digestive system, where enzymes called lipases break down dietary fats into smaller molecules called fatty acids and glycerol. These molecules are then absorbed into the bloodstream and transported to the liver, which is the main site of lipid metabolism.
In the liver, fatty acids may be further broken down for energy production or used to synthesize new lipids. Excess fatty acids may be stored as triglycerides in specialized cells called adipocytes (fat cells) for later use. Cholesterol is also metabolized in the liver, where it may be used to synthesize bile acids, steroid hormones, and other important molecules.
Disorders of lipid metabolism can lead to a range of health problems, including obesity, diabetes, cardiovascular disease, and non-alcoholic fatty liver disease (NAFLD). These conditions may be caused by genetic factors, lifestyle habits, or a combination of both. Proper diagnosis and management of lipid metabolism disorders typically involves a combination of dietary changes, exercise, and medication.
Mitochondrial degradation, also known as mitophagy, is a process by which damaged or dysfunctional mitochondria are eliminated from the cell. Mitochondria are essential organelles that generate energy for the cell through a process called oxidative phosphorylation. However, they can become damaged due to various factors such as mutations in mitochondrial DNA, oxidative stress, or protein misfolding.
Mitophagy is a selective form of autophagy, which is the process by which cells break down and recycle their own components. During mitophagy, damaged mitochondria are tagged with ubiquitin molecules, which serve as a signal for their recognition and engulfment by autophagosomes. Autophagosomes are double-membraned vesicles that enclose cellular components and fuse with lysosomes, where the contents are broken down and recycled.
Mitophagy plays an important role in maintaining mitochondrial quality control and preventing the accumulation of damaged mitochondria, which can lead to cellular dysfunction and disease. Defects in mitophagy have been implicated in various pathologies, including neurodegenerative disorders, cardiovascular diseases, and aging-related conditions.
Arabidopsis proteins refer to the proteins that are encoded by the genes in the Arabidopsis thaliana plant, which is a model organism commonly used in plant biology research. This small flowering plant has a compact genome and a short life cycle, making it an ideal subject for studying various biological processes in plants.
Arabidopsis proteins play crucial roles in many cellular functions, such as metabolism, signaling, regulation of gene expression, response to environmental stresses, and developmental processes. Research on Arabidopsis proteins has contributed significantly to our understanding of plant biology and has provided valuable insights into the molecular mechanisms underlying various agronomic traits.
Some examples of Arabidopsis proteins include transcription factors, kinases, phosphatases, receptors, enzymes, and structural proteins. These proteins can be studied using a variety of techniques, such as biochemical assays, protein-protein interaction studies, and genetic approaches, to understand their functions and regulatory mechanisms in plants.
A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.
Tertiary protein structure refers to the three-dimensional arrangement of all the elements (polypeptide chains) of a single protein molecule. It is the highest level of structural organization and results from interactions between various side chains (R groups) of the amino acids that make up the protein. These interactions, which include hydrogen bonds, ionic bonds, van der Waals forces, and disulfide bridges, give the protein its unique shape and stability, which in turn determines its function. The tertiary structure of a protein can be stabilized by various factors such as temperature, pH, and the presence of certain ions. Any changes in these factors can lead to denaturation, where the protein loses its tertiary structure and thus its function.
Acridine Orange is a fluorescent dye commonly used in various scientific applications, particularly in the field of cytology and microbiology. Its chemical formula is C17H19N3O.
In medical terms, Acridine Orange is often used as a supravital stain to differentiate between live and dead cells or to identify bacteria, fungi, and other microorganisms in samples. It can also be used to detect abnormalities in DNA and RNA, making it useful in the identification of certain types of cancerous cells.
When exposed to ultraviolet light, Acridine Orange exhibits a green fluorescence when bound to double-stranded DNA and a red or orange-red fluorescence when bound to single-stranded RNA. This property makes it a valuable tool in the study of cell division, gene expression, and other biological processes that involve nucleic acids.
However, it is important to note that Acridine Orange can be toxic to living cells in high concentrations or with prolonged exposure, so it must be used carefully and in accordance with established safety protocols.
A plant cell is defined as a type of eukaryotic cell that makes up the structural basis of plants and other forms of multicellular plant-like organisms, such as algae and mosses. These cells are typically characterized by their rigid cell walls, which provide support and protection, and their large vacuoles, which store nutrients and help maintain turgor pressure within the cell.
Plant cells also contain chloroplasts, organelles that carry out photosynthesis and give plants their green color. Other distinctive features of plant cells include a large central vacuole, a complex system of membranes called the endoplasmic reticulum, and numerous mitochondria, which provide energy to the cell through cellular respiration.
Plant cells are genetically distinct from animal cells, and they have unique structures and functions that allow them to carry out photosynthesis, grow and divide, and respond to their environment. Understanding the structure and function of plant cells is essential for understanding how plants grow, develop, and interact with their surroundings.
Proteomics is the large-scale study and analysis of proteins, including their structures, functions, interactions, modifications, and abundance, in a given cell, tissue, or organism. It involves the identification and quantification of all expressed proteins in a biological sample, as well as the characterization of post-translational modifications, protein-protein interactions, and functional pathways. Proteomics can provide valuable insights into various biological processes, diseases, and drug responses, and has applications in basic research, biomedicine, and clinical diagnostics. The field combines various techniques from molecular biology, chemistry, physics, and bioinformatics to study proteins at a systems level.
Multivesicular bodies (MVBs) are membrane-bound organelles found within eukaryotic cells, including animal and human cells. They are involved in the transport and disposal of cellular components, such as proteins and lipids. MVBs are characterized by the presence of multiple intraluminal vesicles (ILVs) contained within a larger compartment. These ILVs form through the inward budding of the limiting membrane, creating a complex internal structure.
MVBs play a crucial role in the process of autophagy, where they help to degrade damaged organelles and protein aggregates by fusing with lysosomes. Additionally, MVBs are essential for the downregulation of cell surface receptors through a process called endocytosis. In this pathway, activated receptors on the plasma membrane are internalized into early endosomes, which then mature into late endosomes or multivesicular bodies. The ILVs within MVBs contain these receptors along with other cellular components, and upon fusion of MVBs with lysosomes, the contents are degraded by hydrolytic enzymes.
In summary, multivesicular bodies (MVBs) are membrane-bound organelles containing multiple intraluminal vesicles that participate in autophagy and endocytosis for the disposal of cellular components and downregulation of surface receptors.
In genetics, sequence alignment is the process of arranging two or more DNA, RNA, or protein sequences to identify regions of similarity or homology between them. This is often done using computational methods to compare the nucleotide or amino acid sequences and identify matching patterns, which can provide insight into evolutionary relationships, functional domains, or potential genetic disorders. The alignment process typically involves adjusting gaps and mismatches in the sequences to maximize the similarity between them, resulting in an aligned sequence that can be visually represented and analyzed.
Protein sorting signals, also known as sorting motifs or sorting determinants, are specific sequences or domains within a protein that determine its intracellular trafficking and localization. These signals can be found in the amino acid sequence of a protein and are recognized by various sorting machinery such as receptors, coat proteins, and transport vesicles. They play a crucial role in directing newly synthesized proteins to their correct destinations within the cell, including the endoplasmic reticulum (ER), Golgi apparatus, lysosomes, plasma membrane, or extracellular space.
There are several types of protein sorting signals, such as:
1. Signal peptides: These are short sequences of amino acids found at the N-terminus of a protein that direct it to the ER for translocation across the membrane and subsequent processing in the secretory pathway.
2. Transmembrane domains: Hydrophobic regions within a protein that span the lipid bilayer, often serving as anchors to tether proteins to specific organelle membranes or the plasma membrane.
3. Glycosylphosphatidylinositol (GPI) anchors: These are post-translational modifications added to the C-terminus of a protein, allowing it to be attached to the outer leaflet of the plasma membrane.
4. Endoplasmic reticulum retrieval signals: KDEL or KKXX-like sequences found at the C-terminus of proteins that direct their retrieval from the Golgi apparatus back to the ER.
5. Lysosomal targeting signals: Sequences within a protein, such as mannose 6-phosphate (M6P) residues or tyrosine-based motifs, that facilitate its recognition and transport to lysosomes.
6. Nuclear localization signals (NLS): Short sequences of basic amino acids that direct a protein to the nuclear pore complex for import into the nucleus.
7. Nuclear export signals (NES): Sequences rich in leucine residues that facilitate the export of proteins from the nucleus to the cytoplasm.
These various targeting and localization signals help ensure that proteins are delivered to their proper destinations within the cell, allowing for the coordinated regulation of cellular processes and functions.
Melanocytes are specialized cells that produce, store, and transport melanin, the pigment responsible for coloring of the skin, hair, and eyes. They are located in the bottom layer of the epidermis (the outermost layer of the skin) and can also be found in the inner ear and the eye's retina. Melanocytes contain organelles called melanosomes, which produce and store melanin.
Melanin comes in two types: eumelanin (black or brown) and pheomelanin (red or yellow). The amount and type of melanin produced by melanocytes determine the color of a person's skin, hair, and eyes. Exposure to UV radiation from sunlight increases melanin production as a protective response, leading to skin tanning.
Melanocyte dysfunction or abnormalities can lead to various medical conditions, such as albinism (lack of melanin production), melasma (excessive pigmentation), and melanoma (cancerous growth of melanocytes).
Acid phosphatase is a type of enzyme that is found in various tissues and organs throughout the body, including the prostate gland, red blood cells, bone, liver, spleen, and kidneys. This enzyme plays a role in several biological processes, such as bone metabolism and the breakdown of molecules like nucleotides and proteins.
Acid phosphatase is classified based on its optimum pH level for activity. Acid phosphatases have an optimal activity at acidic pH levels (below 7.0), while alkaline phosphatases have an optimal activity at basic or alkaline pH levels (above 7.0).
In clinical settings, measuring the level of acid phosphatase in the blood can be useful as a tumor marker for prostate cancer. Elevated acid phosphatase levels may indicate the presence of metastatic prostate cancer or disease progression. However, it is important to note that acid phosphatase is not specific to prostate cancer and can also be elevated in other conditions, such as bone diseases, liver disorders, and some benign conditions. Therefore, acid phosphatase should be interpreted in conjunction with other diagnostic tests and clinical findings for a more accurate diagnosis.
I'd be happy to help! However, I believe there might be a slight misunderstanding in your question. Mitochondria are organelles found in the cells of all complex living organisms, including humans, while the liver is a large, solid organ located in the upper right portion of the abdomen. They don't have a medical definition together. I can certainly provide you with separate definitions for each:
1. Mitochondria: These are double-membrane-bound cellular organelles that generate most of the chemical energy needed to power the cell's biochemical reactions. Commonly known as the "powerhouse of the cell," mitochondria convert organic substrates, such as glucose, fatty acids, and amino acids, into adenosine triphosphate (ATP) through a process called oxidative phosphorylation. Mitochondria are dynamic structures that can change their shape, size, and number through fission (division) and fusion (merging) processes. They play essential roles in various cellular functions, including calcium signaling, apoptosis (programmed cell death), and the regulation of cellular metabolism.
2. Liver: The liver is a large, lobulated organ that lies mainly in the upper right portion of the abdominal cavity, just below the diaphragm. It plays a crucial role in various physiological functions, such as detoxification, protein synthesis, metabolism, and nutrient storage. The liver is responsible for removing toxins from the bloodstream, producing bile to aid in digestion, regulating glucose levels, synthesizing plasma proteins, and storing glycogen, vitamins, and minerals. It also contributes to the metabolism of carbohydrates, lipids, and amino acids, helping maintain energy homeostasis in the body.
I hope this clarifies any confusion! If you have any further questions or need more information, please don't hesitate to ask.
Nocodazole is not a medical condition or disease, but rather a pharmacological agent used in medical research and clinical settings. It's a synthetic chemical compound that belongs to the class of drugs known as microtubule inhibitors. Nocodazole works by binding to and disrupting the dynamic assembly and disassembly of microtubules, which are important components of the cell's cytoskeleton and play a critical role in cell division.
Nocodazole is primarily used in research settings as a tool for studying cell biology and mitosis, the process by which cells divide. It can be used to synchronize cells in the cell cycle or to induce mitotic arrest, making it useful for investigating various aspects of cell division and chromosome behavior.
In clinical settings, nocodazole has been used off-label as a component of some cancer treatment regimens, particularly in combination with other chemotherapeutic agents. Its ability to disrupt microtubules can interfere with the proliferation of cancer cells and enhance the effectiveness of certain anti-cancer drugs. However, its use is not widespread due to potential side effects and the availability of alternative treatments.
"Magnetospirillum" is a genus of bacteria that are capable of magnetotaxis, which means they can align and move along the magnetic field lines of the Earth. They possess unique structures called magnetosomes, which are membrane-enclosed magnetic nanocrystals. These nanocrystals act as intracellular compasses, helping the bacteria navigate through their environment. The genus Magnetospirillum includes several species, such as Magnetospirillum magneticum and Magnetospirillum gryphiswaldense, which are commonly used in research to study bacterial magnetotaxis, biomineralization, and other microbiological processes.
GTP (Guanosine Triphosphate) Phosphohydrolases are a group of enzymes that catalyze the hydrolysis of GTP to GDP (Guanosine Diphosphate) and inorganic phosphate. This reaction plays a crucial role in regulating various cellular processes, including signal transduction pathways, protein synthesis, and vesicle trafficking.
The human genome encodes several different types of GTP Phosphohydrolases, such as GTPase-activating proteins (GAPs), GTPase effectors, and G protein-coupled receptors (GPCRs). These enzymes share a common mechanism of action, in which they utilize the energy released from GTP hydrolysis to drive conformational changes that enable them to interact with downstream effector molecules and modulate their activity.
Dysregulation of GTP Phosphohydrolases has been implicated in various human diseases, including cancer, neurodegenerative disorders, and infectious diseases. Therefore, understanding the structure, function, and regulation of these enzymes is essential for developing novel therapeutic strategies to target these conditions.
Tubulin is a type of protein that forms microtubules, which are hollow cylindrical structures involved in the cell's cytoskeleton. These structures play important roles in various cellular processes, including maintaining cell shape, cell division, and intracellular transport. There are two main types of tubulin proteins: alpha-tubulin and beta-tubulin. They polymerize to form heterodimers, which then assemble into microtubules. The assembly and disassembly of microtubules are dynamic processes that are regulated by various factors, including GTP hydrolysis, motor proteins, and microtubule-associated proteins (MAPs). Tubulin is an essential component of the eukaryotic cell and has been a target for anti-cancer drugs such as taxanes and vinca alkaloids.
Ciliophora is a phylum in the taxonomic classification system that consists of unicellular organisms commonly known as ciliates. These are characterized by the presence of hair-like structures called cilia, which are attached to the cell surface and beat in a coordinated manner to facilitate movement and feeding. Ciliophora includes a diverse group of organisms, many of which are found in aquatic environments. Examples of ciliates include Paramecium, Tetrahymena, and Vorticella.
Trypanosoma brucei brucei is a species of protozoan flagellate parasite that causes African trypanosomiasis, also known as sleeping sickness in humans and Nagana in animals. This parasite is transmitted through the bite of an infected tsetse fly (Glossina spp.). The life cycle of T. b. brucei involves two main stages: the insect-dwelling procyclic trypomastigote stage and the mammalian-dwelling bloodstream trypomastigote stage.
The distinguishing feature of T. b. brucei is its ability to change its surface coat, which helps it evade the host's immune system. This allows the parasite to establish a long-term infection in the mammalian host. However, T. b. brucei is not infectious to humans; instead, two other subspecies, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, are responsible for human African trypanosomiasis.
In summary, Trypanosoma brucei brucei is a non-human-infective subspecies of the parasite that causes African trypanosomiasis in animals and serves as an essential model organism for understanding the biology and pathogenesis of related human-infective trypanosomes.
Adenosine triphosphatases (ATPases) are a group of enzymes that catalyze the conversion of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate. This reaction releases energy, which is used to drive various cellular processes such as muscle contraction, transport of ions across membranes, and synthesis of proteins and nucleic acids.
ATPases are classified into several types based on their structure, function, and mechanism of action. Some examples include:
1. P-type ATPases: These ATPases form a phosphorylated intermediate during the reaction cycle and are involved in the transport of ions across membranes, such as the sodium-potassium pump and calcium pumps.
2. F-type ATPases: These ATPases are found in mitochondria, chloroplasts, and bacteria, and are responsible for generating a proton gradient across the membrane, which is used to synthesize ATP.
3. V-type ATPases: These ATPases are found in vacuolar membranes and endomembranes, and are involved in acidification of intracellular compartments.
4. A-type ATPases: These ATPases are found in the plasma membrane and are involved in various functions such as cell signaling and ion transport.
Overall, ATPases play a crucial role in maintaining the energy balance of cells and regulating various physiological processes.
Rhodophyta, also known as red algae, is a division of simple, multicellular and complex marine algae. These organisms are characterized by their red pigmentation due to the presence of phycobiliproteins, specifically R-phycoerythrin and phycocyanin. They lack flagella and centrioles at any stage of their life cycle. The cell walls of Rhodophyta contain cellulose and various sulphated polysaccharides. Some species have calcium carbonate deposits in their cell walls, which contribute to the formation of coral reefs. Reproduction in these organisms is typically alternation of generations with a dominant gametophyte generation. They are an important source of food for many marine animals and have commercial value as well, particularly for the production of agar, carrageenan, and other products used in the food, pharmaceutical, and cosmetic industries.
In the context of medicine and healthcare, "movement" refers to the act or process of changing physical location or position. It involves the contraction and relaxation of muscles, which allows for the joints to move and the body to be in motion. Movement can also refer to the ability of a patient to move a specific body part or limb, which is assessed during physical examinations. Additionally, "movement" can describe the progression or spread of a disease within the body.
The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:
1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.
Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.
Chediak-Higashi Syndrome is a rare autosomal recessive disorder characterized by partial albinism, photophobia, bleeding diathesis, recurrent infections, and progressive neurological degeneration. It is caused by mutations in the LYST gene, which leads to abnormalities in lysosomes, melanosomes, and neutrophil granules. The disorder is named after two Mexican hematologists, Dr. Chediak and Dr. Higashi, who first described it in 1952.
The symptoms of Chediak-Higashi Syndrome typically appear in early childhood and include light skin and hair, blue or gray eyes, and a sensitivity to light. Affected individuals may also have bleeding problems due to abnormal platelets, and they are prone to recurrent bacterial infections, particularly of the skin, gums, and respiratory system.
The neurological symptoms of Chediak-Higashi Syndrome can include poor coordination, difficulty walking, and seizures. The disorder can also affect the immune system, leading to an accelerated phase known as the "hemophagocytic syndrome," which is characterized by fever, enlarged liver and spleen, and abnormal blood counts.
There is no cure for Chediak-Higashi Syndrome, and treatment typically focuses on managing the symptoms of the disorder. This may include antibiotics to treat infections, medications to control bleeding, and physical therapy to help with mobility issues. In some cases, bone marrow transplantation may be recommended as a potential cure for the disorder.
In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."
1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.
2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.
3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.
4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).
Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.
Immunoblotting, also known as western blotting, is a laboratory technique used in molecular biology and immunogenetics to detect and quantify specific proteins in a complex mixture. This technique combines the electrophoretic separation of proteins by gel electrophoresis with their detection using antibodies that recognize specific epitopes (protein fragments) on the target protein.
The process involves several steps: first, the protein sample is separated based on size through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Next, the separated proteins are transferred onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric field. The membrane is then blocked with a blocking agent to prevent non-specific binding of antibodies.
After blocking, the membrane is incubated with a primary antibody that specifically recognizes the target protein. Following this, the membrane is washed to remove unbound primary antibodies and then incubated with a secondary antibody conjugated to an enzyme such as horseradish peroxidase (HRP) or alkaline phosphatase (AP). The enzyme catalyzes a colorimetric or chemiluminescent reaction that allows for the detection of the target protein.
Immunoblotting is widely used in research and clinical settings to study protein expression, post-translational modifications, protein-protein interactions, and disease biomarkers. It provides high specificity and sensitivity, making it a valuable tool for identifying and quantifying proteins in various biological samples.
Chloroplast DNA (cpDNA) refers to the genetic material present in the chloroplasts, which are organelles found in the cells of photosynthetic organisms such as plants, algae, and some bacteria. Chloroplasts are responsible for capturing sunlight energy and converting it into chemical energy through the process of photosynthesis.
Chloroplast DNA is circular and contains a small number of genes compared to the nuclear genome. It encodes for some of the essential components required for chloroplast function, including proteins involved in photosynthesis, transcription, and translation. The majority of chloroplast proteins are encoded by the nuclear genome and are imported into the chloroplast after being synthesized in the cytoplasm.
Chloroplast DNA is inherited maternally in most plants, meaning that it is passed down from the maternal parent to their offspring through the egg cell. This mode of inheritance has been used in plant breeding and genetic engineering to introduce desirable traits into crops.
Scanning electron microscopy (SEM) is a type of electron microscopy that uses a focused beam of electrons to scan the surface of a sample and produce a high-resolution image. In SEM, a beam of electrons is scanned across the surface of a specimen, and secondary electrons are emitted from the sample due to interactions between the electrons and the atoms in the sample. These secondary electrons are then detected by a detector and used to create an image of the sample's surface topography. SEM can provide detailed images of the surface of a wide range of materials, including metals, polymers, ceramics, and biological samples. It is commonly used in materials science, biology, and electronics for the examination and analysis of surfaces at the micro- and nanoscale.
Centrifugation is a laboratory technique that involves the use of a machine called a centrifuge to separate mixtures based on their differing densities or sizes. The mixture is placed in a rotor and spun at high speeds, causing the denser components to move away from the center of rotation and the less dense components to remain nearer the center. This separation allows for the recovery and analysis of specific particles, such as cells, viruses, or subcellular organelles, from complex mixtures.
The force exerted on the mixture during centrifugation is described in terms of relative centrifugal force (RCF) or g-force, which represents the number of times greater the acceleration due to centrifugation is than the acceleration due to gravity. The RCF is determined by the speed of rotation (revolutions per minute, or RPM), the radius of rotation, and the duration of centrifugation.
Centrifugation has numerous applications in various fields, including clinical laboratories, biochemistry, molecular biology, and virology. It is a fundamental technique for isolating and concentrating particles from solutions, enabling further analysis and characterization.
Video microscopy is a medical technique that involves the use of a microscope equipped with a video camera to capture and display real-time images of specimens on a monitor. This allows for the observation and documentation of dynamic processes, such as cell movement or chemical reactions, at a level of detail that would be difficult or impossible to achieve with the naked eye. Video microscopy can also be used in conjunction with image analysis software to measure various parameters, such as size, shape, and motion, of individual cells or structures within the specimen.
There are several types of video microscopy, including brightfield, darkfield, phase contrast, fluorescence, and differential interference contrast (DIC) microscopy. Each type uses different optical techniques to enhance contrast and reveal specific features of the specimen. For example, fluorescence microscopy uses fluorescent dyes or proteins to label specific structures within the specimen, allowing them to be visualized against a dark background.
Video microscopy is used in various fields of medicine, including pathology, microbiology, and neuroscience. It can help researchers and clinicians diagnose diseases, study disease mechanisms, develop new therapies, and understand fundamental biological processes at the cellular and molecular level.
Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.
Biological transport, active is the process by which cells use energy to move materials across their membranes from an area of lower concentration to an area of higher concentration. This type of transport is facilitated by specialized proteins called transporters or pumps that are located in the cell membrane. These proteins undergo conformational changes to physically carry the molecules through the lipid bilayer of the membrane, often against their concentration gradient.
Active transport requires energy because it works against the natural tendency of molecules to move from an area of higher concentration to an area of lower concentration, a process known as diffusion. Cells obtain this energy in the form of ATP (adenosine triphosphate), which is produced through cellular respiration.
Examples of active transport include the uptake of glucose and amino acids into cells, as well as the secretion of hormones and neurotransmitters. The sodium-potassium pump, which helps maintain resting membrane potential in nerve and muscle cells, is a classic example of an active transporter.
Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:
1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.
Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.
Phase-contrast microscopy is a type of optical microscopy that allows visualization of transparent or translucent specimens, such as living cells and their organelles, by increasing the contrast between areas with different refractive indices within the sample. This technique works by converting phase shifts in light passing through the sample into changes in amplitude, which can then be observed as differences in brightness and contrast.
In a phase-contrast microscope, a special condenser and objective are used to create an optical path difference between the direct and diffracted light rays coming from the specimen. The condenser introduces a phase shift for the diffracted light, while the objective contains a phase ring that compensates for this shift in the direct light. This results in the direct light appearing brighter than the diffracted light, creating contrast between areas with different refractive indices within the sample.
Phase-contrast microscopy is particularly useful for observing unstained living cells and their dynamic processes, such as cell division, motility, and secretion, without the need for stains or dyes that might affect their viability or behavior.
Cytochalasins are a group of fungal metabolites that have the ability to disrupt the organization and dynamics of the cytoskeleton in eukaryotic cells. They bind to the barbed end of actin filaments, preventing the addition or loss of actin subunits, which results in the inhibition of actin polymerization and depolymerization. This can lead to changes in cell shape, motility, and cytokinesis (the process by which a cell divides into two daughter cells).
There are several different types of cytochalasins, including cytochalasin A, B, C, D, and E, among others. Each type has slightly different effects on the actin cytoskeleton and may also have other cellular targets. Cytochalasins have been widely used in research to study the role of the actin cytoskeleton in various cellular processes.
In addition to their use in research, cytochalasins have also been investigated for their potential therapeutic applications. For example, some studies have suggested that cytochalasins may have anti-cancer properties by inhibiting the proliferation and migration of cancer cells. However, more research is needed before these compounds can be developed into effective treatments for human diseases.
The proteome is the entire set of proteins produced or present in an organism, system, organ, or cell at a certain time under specific conditions. It is a dynamic collection of protein species that changes over time, responding to various internal and external stimuli such as disease, stress, or environmental factors. The study of the proteome, known as proteomics, involves the identification and quantification of these protein components and their post-translational modifications, providing valuable insights into biological processes, functional pathways, and disease mechanisms.
A proton pump is a specialized protein structure that functions as an enzyme, known as a proton pump ATPase, which actively transports hydrogen ions (protons) across a membrane. This process creates a gradient of hydrogen ions, resulting in an electrochemical potential difference, also known as a proton motive force. The main function of proton pumps is to generate and maintain this gradient, which can be used for various purposes, such as driving the synthesis of ATP (adenosine triphosphate) or transporting other molecules against their concentration gradients.
In the context of gastric physiology, the term "proton pump" often refers to the H+/K+-ATPase present in the parietal cells of the stomach. This proton pump is responsible for secreting hydrochloric acid into the stomach lumen, contributing to the digestion and sterilization of ingested food. Inhibiting this specific proton pump with medications like proton pump inhibitors (PPIs) is a common treatment strategy for gastric acid-related disorders such as gastroesophageal reflux disease (GERD), peptic ulcers, and Zollinger-Ellison syndrome.
Synaptic vesicles are tiny membrane-enclosed sacs within the presynaptic terminal of a neuron, containing neurotransmitters. They play a crucial role in the process of neurotransmission, which is the transmission of signals between nerve cells. When an action potential reaches the presynaptic terminal, it triggers the fusion of synaptic vesicles with the plasma membrane, releasing neurotransmitters into the synaptic cleft. These neurotransmitters can then bind to receptors on the postsynaptic neuron and trigger a response. After release, synaptic vesicles are recycled through endocytosis, allowing them to be refilled with neurotransmitters and used again in subsequent rounds of neurotransmission.
Fungal proteins are a type of protein that is specifically produced and present in fungi, which are a group of eukaryotic organisms that include microorganisms such as yeasts and molds. These proteins play various roles in the growth, development, and survival of fungi. They can be involved in the structure and function of fungal cells, metabolism, pathogenesis, and other cellular processes. Some fungal proteins can also have important implications for human health, both in terms of their potential use as therapeutic targets and as allergens or toxins that can cause disease.
Fungal proteins can be classified into different categories based on their functions, such as enzymes, structural proteins, signaling proteins, and toxins. Enzymes are proteins that catalyze chemical reactions in fungal cells, while structural proteins provide support and protection for the cell. Signaling proteins are involved in communication between cells and regulation of various cellular processes, and toxins are proteins that can cause harm to other organisms, including humans.
Understanding the structure and function of fungal proteins is important for developing new treatments for fungal infections, as well as for understanding the basic biology of fungi. Research on fungal proteins has led to the development of several antifungal drugs that target specific fungal enzymes or other proteins, providing effective treatment options for a range of fungal diseases. Additionally, further study of fungal proteins may reveal new targets for drug development and help improve our ability to diagnose and treat fungal infections.
Propanediol Dehydratase is not a medical term per se, but rather a biochemical term. It refers to an enzyme that catalyzes the conversion of 1,2-propanediol (also known as propylene glycol) into propionaldehyde and water in the metabolic pathway known as the glycerol/propanediol utilization (GUD) system.
The reaction catalyzed by Propanediol Dehydratase is:
(CH3)2CH(OH)CH2OH → CH3CH2CHO + H2O
This enzyme is found in certain bacteria and archaea that are capable of utilizing 1,2-propanediol as a carbon source for growth. Deficiency or absence of this enzyme can affect the metabolic capabilities of these microorganisms.
I'm not a medical expert, but I can provide you with some information about algal DNA.
Algal DNA refers to the genetic material found in algae, which are simple, photosynthetic organisms that live in various aquatic environments. The DNA of algae is similar to that of other living organisms, as it carries the genetic instructions necessary for the growth, development, and reproduction of these single-celled or multicellular life forms.
Algal DNA can be found in different types of algae, including:
1. Chlorophyta (green algae)
2. Rhodophyta (red algae)
3. Phaeophyceae (brown algae)
4. Cyanobacteria (blue-green algae or cyanoprokaryotes, which are actually bacteria with photosynthetic capabilities)
These different groups of algae have unique characteristics and ecological roles in their environments. Studying the DNA of algae can help researchers understand their evolutionary relationships, genetic diversity, and potential applications in various fields such as biotechnology, bioenergy, and environmental science.
Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.
Bacterial proteins can be classified into different categories based on their function, such as:
1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.
Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.
In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.
For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.
Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.
Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.
Macrolides are a class of antibiotics derived from natural products obtained from various species of Streptomyces bacteria. They have a large ring structure consisting of 12, 14, or 15 atoms, to which one or more sugar molecules are attached. Macrolides inhibit bacterial protein synthesis by binding to the 50S ribosomal subunit, thereby preventing peptide bond formation. Common examples of macrolides include erythromycin, azithromycin, and clarithromycin. They are primarily used to treat respiratory, skin, and soft tissue infections caused by susceptible gram-positive and gram-negative bacteria.
Microscopy is a technical field in medicine that involves the use of microscopes to observe structures and phenomena that are too small to be seen by the naked eye. It allows for the examination of samples such as tissues, cells, and microorganisms at high magnifications, enabling the detection and analysis of various medical conditions, including infections, diseases, and cellular abnormalities.
There are several types of microscopy used in medicine, including:
1. Light Microscopy: This is the most common type of microscopy, which uses visible light to illuminate and magnify samples. It can be used to examine a wide range of biological specimens, such as tissue sections, blood smears, and bacteria.
2. Electron Microscopy: This type of microscopy uses a beam of electrons instead of light to produce highly detailed images of samples. It is often used in research settings to study the ultrastructure of cells and tissues.
3. Fluorescence Microscopy: This technique involves labeling specific molecules within a sample with fluorescent dyes, allowing for their visualization under a microscope. It can be used to study protein interactions, gene expression, and cell signaling pathways.
4. Confocal Microscopy: This type of microscopy uses a laser beam to scan a sample point by point, producing high-resolution images with reduced background noise. It is often used in medical research to study the structure and function of cells and tissues.
5. Scanning Probe Microscopy: This technique involves scanning a sample with a physical probe, allowing for the measurement of topography, mechanical properties, and other characteristics at the nanoscale. It can be used in medical research to study the structure and function of individual molecules and cells.
A centrosome is a microtubule-organizing center found in animal cells. It consists of two barrel-shaped structures called centrioles, which are surrounded by a protein matrix called the pericentriolar material. The centrosome plays a crucial role in organizing the microtubules that form the cell's cytoskeleton and help to shape the cell, as well as in separating the chromosomes during cell division.
During mitosis, the two centrioles of the centrosome separate and move to opposite poles of the cell, where they nucleate the formation of the spindle fibers that pull the chromosomes apart. The centrosome also helps to ensure that the genetic material is equally distributed between the two resulting daughter cells.
It's worth noting that while centrioles are present in many animal cells, they are not always present in all types of cells. For example, plant cells do not have centrioles or centrosomes, and instead rely on other mechanisms to organize their microtubules.
Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).
The Western blotting procedure involves several steps:
1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.
Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.
"Mycoplasma pneumoniae" is a type of bacteria that lacks a cell wall and can cause respiratory infections, particularly bronchitis and atypical pneumonia. It is one of the most common causes of community-acquired pneumonia. Infection with "M. pneumoniae" typically results in mild symptoms, such as cough, fever, and fatigue, although more severe complications can occur in some cases. The bacteria can also cause various extrapulmonary manifestations, including skin rashes, joint pain, and neurological symptoms. Diagnosis of "M. pneumoniae" infection is typically made through serological tests or PCR assays. Treatment usually involves antibiotics such as macrolides or tetracyclines.
Post-translational protein processing refers to the modifications and changes that proteins undergo after their synthesis on ribosomes, which are complex molecular machines responsible for protein synthesis. These modifications occur through various biochemical processes and play a crucial role in determining the final structure, function, and stability of the protein.
The process begins with the translation of messenger RNA (mRNA) into a linear polypeptide chain, which is then subjected to several post-translational modifications. These modifications can include:
1. Proteolytic cleavage: The removal of specific segments or domains from the polypeptide chain by proteases, resulting in the formation of mature, functional protein subunits.
2. Chemical modifications: Addition or modification of chemical groups to the side chains of amino acids, such as phosphorylation (addition of a phosphate group), glycosylation (addition of sugar moieties), methylation (addition of a methyl group), acetylation (addition of an acetyl group), and ubiquitination (addition of a ubiquitin protein).
3. Disulfide bond formation: The oxidation of specific cysteine residues within the polypeptide chain, leading to the formation of disulfide bonds between them. This process helps stabilize the three-dimensional structure of proteins, particularly in extracellular environments.
4. Folding and assembly: The acquisition of a specific three-dimensional conformation by the polypeptide chain, which is essential for its function. Chaperone proteins assist in this process to ensure proper folding and prevent aggregation.
5. Protein targeting: The directed transport of proteins to their appropriate cellular locations, such as the nucleus, mitochondria, endoplasmic reticulum, or plasma membrane. This is often facilitated by specific signal sequences within the protein that are recognized and bound by transport machinery.
Collectively, these post-translational modifications contribute to the functional diversity of proteins in living organisms, allowing them to perform a wide range of cellular processes, including signaling, catalysis, regulation, and structural support.
Homeostasis is a fundamental concept in the field of medicine and physiology, referring to the body's ability to maintain a stable internal environment, despite changes in external conditions. It is the process by which biological systems regulate their internal environment to remain in a state of dynamic equilibrium. This is achieved through various feedback mechanisms that involve sensors, control centers, and effectors, working together to detect, interpret, and respond to disturbances in the system.
For example, the body maintains homeostasis through mechanisms such as temperature regulation (through sweating or shivering), fluid balance (through kidney function and thirst), and blood glucose levels (through insulin and glucagon secretion). When homeostasis is disrupted, it can lead to disease or dysfunction in the body.
In summary, homeostasis is the maintenance of a stable internal environment within biological systems, through various regulatory mechanisms that respond to changes in external conditions.
Synaptophysin is a protein found in the presynaptic vesicles of neurons, which are involved in the release of neurotransmitters during synaptic transmission. It is often used as a marker for neuronal differentiation and is widely expressed in neuroendocrine cells and tumors. Synaptophysin plays a role in the regulation of neurotransmitter release and has been implicated in various neurological disorders, including Alzheimer's disease and synaptic dysfunction-related conditions.
A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.
Cercozoa is a major group of predominantly heterotrophic protists that are characterized by the presence of unique feeding structures called "cercomonads" or "filose pseudopodia." These pseudopods are thin, filamentous extensions used for capturing and engulfing prey. Cercozoa includes a wide variety of species, many of which are important decomposers and contributors to nutrient cycling in aquatic and terrestrial environments. Some members of this group can form symbiotic relationships with other organisms or have the ability to photosynthesize through endosymbiosis with algae. Due to their diverse morphology, ecological roles, and molecular characteristics, Cercozoa has been challenging to define and classify precisely, but recent advances in molecular phylogeny have helped clarify its position within the eukaryotic tree of life.
Molecular evolution is the process of change in the DNA sequence or protein structure over time, driven by mechanisms such as mutation, genetic drift, gene flow, and natural selection. It refers to the evolutionary study of changes in DNA, RNA, and proteins, and how these changes accumulate and lead to new species and diversity of life. Molecular evolution can be used to understand the history and relationships among different organisms, as well as the functional consequences of genetic changes.
Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.
The rough endoplasmic reticulum (RER) is a type of organelle found in eukaryotic cells, which are characterized by the presence of ribosomes on their cytoplasmic surface. These ribosomes give the RER a "rough" appearance and are responsible for the synthesis of proteins that are destined to be exported from the cell or targeted to various organelles within the cell.
The RER is involved in several important cellular processes, including:
1. Protein folding and modification: Once proteins are synthesized by ribosomes on the RER, they are transported into the lumen of the RER where they undergo folding and modifications such as glycosylation.
2. Quality control: The RER plays a crucial role in ensuring that only properly folded and modified proteins are transported to their final destinations within the cell or exported from the cell. Misfolded or improperly modified proteins are retained within the RER and targeted for degradation.
3. Transport: Proteins that are synthesized on the RER are packaged into vesicles and transported to the Golgi apparatus, where they undergo further modifications and sorting before being transported to their final destinations.
Overall, the rough endoplasmic reticulum is a critical organelle for protein synthesis, folding, modification, and transport in eukaryotic cells.
'Staining and labeling' are techniques commonly used in pathology, histology, cytology, and molecular biology to highlight or identify specific components or structures within tissues, cells, or molecules. These methods enable researchers and medical professionals to visualize and analyze the distribution, localization, and interaction of biological entities, contributing to a better understanding of diseases, cellular processes, and potential therapeutic targets.
Medical definitions for 'staining' and 'labeling' are as follows:
1. Staining: A process that involves applying dyes or stains to tissues, cells, or molecules to enhance their contrast and reveal specific structures or components. Stains can be categorized into basic stains (which highlight acidic structures) and acidic stains (which highlight basic structures). Common staining techniques include Hematoxylin and Eosin (H&E), which differentiates cell nuclei from the surrounding cytoplasm and extracellular matrix; special stains, such as PAS (Periodic Acid-Schiff) for carbohydrates or Masson's trichrome for collagen fibers; and immunostains, which use antibodies to target specific proteins.
2. Labeling: A process that involves attaching a detectable marker or tag to a molecule of interest, allowing its identification, quantification, or tracking within a biological system. Labels can be direct, where the marker is directly conjugated to the targeting molecule, or indirect, where an intermediate linker molecule is used to attach the label to the target. Common labeling techniques include fluorescent labels (such as FITC, TRITC, or Alexa Fluor), enzymatic labels (such as horseradish peroxidase or alkaline phosphatase), and radioactive labels (such as ³²P or ¹⁴C). Labeling is often used in conjunction with staining techniques to enhance the specificity and sensitivity of detection.
Together, staining and labeling provide valuable tools for medical research, diagnostics, and therapeutic development, offering insights into cellular and molecular processes that underlie health and disease.
Time-lapse imaging is a medical imaging technique where images are captured at regular intervals over a period of time and then played back at a faster rate to show the progression or changes that occur during that time frame. This technique is often used in various fields of medicine, including microbiology, pathology, and reproductive medicine. In microbiology, for example, time-lapse imaging can be used to observe bacterial growth or the movement of individual cells. In pathology, it might help track the development of a lesion or the response of a tumor to treatment. In reproductive medicine, time-lapse imaging is commonly employed in embryo culture during in vitro fertilization (IVF) procedures to assess the development and quality of embryos before implantation.
Mesophyll cells are photosynthetic cells located in the interior tissue of a leaf, specifically within the chloroplast-containing portion called the mesophyll. These cells are responsible for capturing sunlight and converting it into chemical energy through the process of photosynthesis. They can be further divided into two types: palisade mesophyll cells and spongy mesophyll cells.
Palisade mesophyll cells are columnar-shaped cells that contain many chloroplasts and are located closer to the upper epidermis of the leaf. They are arranged in one or more layers and are primarily responsible for capturing light during photosynthesis.
Spongy mesophyll cells, on the other hand, are loosely arranged and have a sponge-like structure. They contain fewer chloroplasts than palisade mesophyll cells and are located closer to the lower epidermis of the leaf. These cells facilitate gas exchange between the plant and the environment by allowing for the diffusion of carbon dioxide into the leaf and oxygen out of the leaf.
Overall, mesophyll cells play a critical role in photosynthesis and help to maintain the health and growth of the plant.
3,3'-Diaminobenzidine (DAB) is a chemical compound that is commonly used as a chromogen in histological and immunohistochemical staining techniques. It is a type of polymerization substrate that reacts with horseradish peroxidase (HRP) to produce an insoluble, dark-brown precipitate at the site of the antigen-antibody reaction. This allows for the visualization and localization of specific proteins or other antigens within tissue sections.
The chemical formula for DAB is C12H12N2O2, and it is a light-sensitive compound that should be handled and stored in a dark environment to prevent unwanted photochemical reactions. It is important to note that DAB is considered a potential carcinogen and should be handled with appropriate safety precautions, including the use of gloves, lab coats, and eye protection.
Organelle
Vault (organelle)
Polar organelle
Organelle biogenesis
Vesiculo-vacuolar organelle
Biogenesis of lysosome-related organelles complex 3
Biogenesis of lysosome-related organelles complex 1
Cytostome
Vesicular-tubular cluster
Acidocalcisome
Jean Vance
Maurer's cleft
Mating bridge
Nematocyst (dinoflagellate)
Microbody
P14 deficiency
Peroxisome
Cell (biology)
Ruth Sager
Symbiosome
Outline of cell biology
Nuclear dimorphism
Symbiodinium
William F. Martin
Otto Kandler
Pre-cell
Kinetoplast
Cryptomonada
RNA editing
Prokaryote
Organelle - Wikipedia
How bacterial organelles assemble | ScienceDaily
ORGANELLES Definition & Usage Examples | Dictionary.com
Optogenetic control of organelle transport and positioning | Nature
Organelles News, Articles | The Scientist Magazine®
Princeton team discovers new organelle involved in cancer metastasis
cell organelles
What is the mitochondrion is the cell organelle responsible for? - Answers
Excessive contact between cellular organelles disrupts metabolism | News | Harvard T.H. Chan School of Public Health
Organelle Marker FAQs | OriGene
organelles - Homework Help Videos - Brightstorm
Cell Component | Lysosome And Related Organelles
MitoCarta3.0: an updated mitochondrial proteome now with sub-organelle localization and pathway annotations
Study Sheds Light on How Bacterial Organelles Assemble - Berkeley Lab - Berkeley Lab News Center
organelle - Ontology Browser - Rat Genome Database
What rules govern the structure of membraneless organelles? - Campaign - University at Buffalo
Membraneless organelles: phasing out of equilibrium | Emerging Topics in Life Sciences | Portland Press
Cellular Organisation: Putting organelles in their place | eLife
Recent Advances in Electron Cryotomography and their Application to Imaging Purified Protein Complexes, Isolated Organelles,...
Bloc1s4 MGI Mouse Gene Detail - MGI:1929230 - biogenesis of lysosomal organelles complex-1, subunit 4, cappuccino
Distinguished Scientist Seminar Series featuring Ebru Erbay, MD, PhD - 'Organelle Stress in Cardiometabolic Disease' -...
Plus it
of Eukaryotic Organelles 10/1/96 Essay - Free Essay Example | Artscolumbia
Comparative analysis of mitochondrion-related organelles in anaerobic amoebozoans | Lund University Publications
Frontiers | The Puzzle of Metabolite Exchange and Identification of Putative Octotrico Peptide Repeat Expression Regulators in...
Organelle Antibody & Stain Selection Guide Poster | Thermo Fisher Scientific - US
Name the organelle of plant cells in which photosynthesis occurs.
Small Things Considered: Sex (Well, Not Really) and the Single Organelle
Apicomplexan-like parasites are polyphyletic and widely but selectively dependent on cryptic plastid organelles | eLife
Chan Group - Plant Organelle and Cellular Signalling | ANU Research School of Biology
Mitochondria18
- Using this definition, there would only be two broad classes of organelles (i.e. those that contain their own DNA, and have originated from endosymbiotic bacteria): mitochondria (in almost all eukaryotes) plastids (e.g. in plants, algae, and some protists). (wikipedia.org)
- We demonstrate that the motility of peroxisomes, recycling endosomes and mitochondria can be locally and repeatedly induced or stopped, allowing rapid organelle repositioning. (nature.com)
- Everybody goes to school, and they learn 'The mitochondria is the powerhouse of the cell,' and a few other things about a few organelles, but now, our classic definition of what's inside a cell, of how a cell organizes itself and controls its behavior, is starting to shift," he said. (princeton.edu)
- The mitochondrion (plural mitochondria) is the cell organelle responsible for energy production. (answers.com)
- They counted each of the contact points between two cellular organelles - the endoplasmic reticulum (ER) and mitochondria - and demonstrated for the first time that the number of these connections, called MAMs, markedly increase during obesity. (harvard.edu)
- While organelles like endoplasmic reticulum (ER) and mitochondria form functionally specialized units, they need to coordinate with each other to provide the metabolic robustness and adaptability needed by the immune cells to transition between activation and resolution phases of inflammation. (georgetown.edu)
- Here, we present a method that allows the measurement of asymmetric organelle partitioning, and we use it to simultaneously measure the partitioning of three kinds of cellular elements, i.e. cytoplasm, membrane, and mitochondria in a proliferating population of human Jurkat T-cells. (biorxiv.org)
- The outer membrane shapes the organelle into its egg-like shape, while the inner membrane folds inward to form a set of shelves" or cristae that allow the reactions of the mitochondria to take place. (artscolumbia.org)
- We emphasized that in the cells of many organisms (which contain more than single organelles) the mitochondria lack permanent iden-tity. (asmblog.org)
- Within the cytoplasm, the major organelles and cellular structures include: (1) nucleolus (2) nucleus (3) ribosome (4) vesicle (5) rough endoplasmic reticulum (6) Golgi apparatus (7) cytoskeleton (8) smooth endoplasmic reticulum (9) mitochondria (10) vacuole (11) cytosol (12) lysosome (13) centriole. (farinelliandthekingbroadway.com)
- Mitochondria: The Best Cell Organelle. (farinelliandthekingbroadway.com)
- Organelle Plant Cells Animal Cells Organelle Cell Wall Mitochondria Vesicle Nucleolus Chloroplast Nucleus Chromatin Plasma membrane Cytoplasm Central vacuole Cytoskeleton Ribosome Endoplasmic reticulum Vacuole Golgi apparatus Lysosome Plant Cells Animal Cells Cell City Analogy In a far away city called Grant City, the main export and production product is the steel widget. (studyres.com)
- Mitochondria are membrane-bound organelles found in the cytoplasm of eukaryotic cells. (biochemden.com)
- Mitochondria are generally oval or sausage-shaped organelles, with a double membrane structure. (biochemden.com)
- The nucleus, endoplasmic reticulum, Golgi apparatus, mitochondria, and plastids are all organelles bound by a double lipid bilayer in a eukaryotic cell. (researchtweet.com)
- The nucleus, endoplasmic reticulum, Golgi apparatus, mitochondria, and chloroplast are just a few of the organelles found in eukaryotic cells (plastids). (researchtweet.com)
- Mitochondria and plastids are the organelles in question. (researchtweet.com)
- Based on these identified molecular targets, we review and discuss the potential of drug development to target organelle dynamics, especially mitochondria dynamics and ER- organelle membrane contact dynamics, in the central nervous system for treating human diseases , including neurodegenerative diseases such as Alzheimer's disease , Parkinson's disease , Huntington's disease and amyotrophic lateral sclerosis . (bvsalud.org)
Endoplasmic reticulum1
- These organelles can float freely in the cytoplasm or be connected to the endoplasmic reticulum (see above). (medlineplus.gov)
Proteins9
- Many of these are referred to as "proteinaceous organelles" as their main structure is made of proteins. (wikipedia.org)
- Far from being inert fat-storage depots within cells, these lipid-loaded organelles recruit immune proteins and block bacterial growth. (the-scientist.com)
- 1. What are the fluorescent proteins used for the organelle markers? (origene.com)
- Lysosomes are membrane-bound organelles containing digestive enzymes that can break down proteins, lipids, carbohydrates and nucleic acids. (cellimagelibrary.org)
- These proteins show similar domain architectures as known organelle-targeted expression regulators of the octotrico peptide repeat type in algae and plants. (frontiersin.org)
- Then, in these two decades, it has been elucidated that various lipids synthesized in the ER are rapidly and accurately delivered to other organelles by a variety of lipid transfer proteins (LTPs) at zones where the ER is in contact with other specific organelles. (centenary.org.au)
- Other organelles help synthesize the proteins needed by the cell. (lumenlearning.com)
- are organelles that process the cell's genetic instructions to create proteins. (medlineplus.gov)
- Specialized cell structures called ribosomes are the cellular organelles that actually synthesize the proteins (RNA transcription). (cdc.gov)
Mitochondrion2
- What is the mitochondrion is the cell organelle responsible for? (answers.com)
- Archamoebae comprises free-living or endobiotic amoebiform protists that inhabit anaerobic or microaerophilic environments and possess mitochondrion-related organelles (MROs) adapted to function anaerobically. (lu.se)
Ribosomes4
- Therefore, the use of organelle to also refer to non-membrane bound structures such as ribosomes is common and accepted. (wikipedia.org)
- The nucleolus is an organelle that makes ribosomes. (lumenlearning.com)
- The non-membrane-bound cytoplasmic structures, such as the nucleolus and ribosomes, are another less-strict definition of an organelle. (researchtweet.com)
- Ribosomes and nucleosomes are not considered organelles in this sense, since they are not confined by membranes. (researchtweet.com)
Subcellular2
- The physical principles that dictate the formation of these subcellular compartments are simple, but they dictate the organelles' complex functions. (the-scientist.com)
- Conventional fluorescent microscope can be used for viewing some of the organelle or subcellular structures. (origene.com)
Found in eukaryotic cells1
- These organelles are found in eukaryotic cells, which are cells that have a nucleus and other membrane-bound organelles. (biochemden.com)
Intracellular4
- For many organelles, however, the precise connection between position and function has remained unclear, because strategies to control intracellular organelle positioning with spatiotemporal precision are lacking. (nature.com)
- Myosin V motors transport organelles to their correct intracellular locations. (rupress.org)
- Although the basic biological mechanism underlying the dynamics of intracellular organelles has been extensively studied, relative drug development is still limited. (bvsalud.org)
- In the present review , we show that due to the development of technical advanced imaging tools, especially live cell imaging methods , intracellular organelle dynamics (including mitochondrial dynamics and membrane contact sites) can be dissected at the molecular level. (bvsalud.org)
Membranes4
- The contents within these organelles determine their specific function, but the overall architecture of the protein membranes of BMCs are fundamentally the same, the authors noted. (sciencedaily.com)
- Lipids are the major constituents of all cell membranes and play dynamic roles in organelle structure and function. (centenary.org.au)
- What is the only organelle that is not bound or made of membranes? (farinelliandthekingbroadway.com)
- this organelle consists of such an extensive network of membranes that it accounts for more than half the total membrane in many cells. (farinelliandthekingbroadway.com)
Biogenesis1
- The biogenesis of lysosome-related organelles complex (BLOC) type 1 and 3 are required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet-dense granules. (medscape.com)
Cell60
- In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. (wikipedia.org)
- Organelles are identified by microscopy, and can also be purified by cell fractionation. (wikipedia.org)
- Also, the prokaryotic flagellum which protrudes outside the cell, and its motor, as well as the largely extracellular pilus, are often spoken of as organelles. (wikipedia.org)
- While most cell biologists consider the term organelle to be synonymous with cell compartment, a space often bound by one or two lipid bilayers, some cell biologists choose to limit the term to include only those cell compartments that contain deoxyribonucleic acid (DNA), having originated from formerly autonomous microscopic organisms acquired via endosymbiosis. (wikipedia.org)
- However, even by using this definition, some parts of the cell that have been shown to be distinct functional units do not qualify as organelles. (wikipedia.org)
- membrane protein complexes: porosome, photosystem I, ATP synthase large DNA and protein complexes: nucleosome centriole and microtubule-organizing center (MTOC) cytoskeleton flagellum nucleolus stress granule germ cell granule neuronal transport granule The mechanisms by which such non-membrane bound organelles form and retain their spatial integrity have been likened to liquid-liquid phase separation. (wikipedia.org)
- The second, more restrictive definition of organelle includes only those cell compartments that contain deoxyribonucleic acid (DNA), having originated from formerly autonomous microscopic organisms acquired via endosymbiosis. (wikipedia.org)
- The University of California, Santa Barbara, cell biologist is investigating the formation and functions of the peroxisome, an organelle which exists in many copies in each cell and can be created, lost, or altered to meet the cell's metabolic needs. (the-scientist.com)
- Not only does their work tie phase separations to cancer research, but the merging blobs turned out to create more than the sum of their parts, self-assembling into a previously unknown organelle (essentially an organ of the cell). (princeton.edu)
- Cell organelle that provides energy to the cell? (answers.com)
- What organelle is most important for providing energy to a cell? (answers.com)
- Organelle that provides most of the ATP needed by the cell is the? (answers.com)
- 7. Can I make stable mammalian cell lines with the organelle markers? (origene.com)
- Lysosomes can vary in size and shape, and function to break down food particles, destroy bacteria and viruses that enter the cell, and to recycle cellular components as organelles age. (cellimagelibrary.org)
- To work correctly, most organelles need to be properly positioned within the cell. (elifesciences.org)
- In this seminar, I will describe our current mechanistic findings that explain how organelle stress alters immune cell functions relevant to atherosclerosis. (georgetown.edu)
- However, in some unicellular organisms one can reasonably say that the number is indeed one of a given type of organelle per cell. (asmblog.org)
- The evidence rests not only on mor-pho-logy but also on the coherence between cell division and organelle division. (asmblog.org)
- They are all obviously harmful to the plant, but what's also fascinating is that they all induce a complex array of organelle and cellular signalling pathways within the plant cell, with unique and overlapping components that enable plants to respond to these perturbations. (edu.au)
- How does lipid transport between organelles in the cell take place and how is it regulated? (centenary.org.au)
- An organelle is a structure within the cell analogous to an organ - specialized components to do specific jobs, allowing the whole cell to function, just like your heart, lungs, and liver do for your whole body. (freethink.com)
- More research may also help us know how the organelle fits into the life of the cell, how it interacts with the others and how it changes over time. (freethink.com)
- Laser microbeam abalation of GFP-labeled nuclear organelles in a living cell. (escholarship.org)
- Organelles are involved in many vital cell functions. (pressbooks.pub)
- What are 4 important cell organelles? (farinelliandthekingbroadway.com)
- What are the 10 most important organelles in a cell? (farinelliandthekingbroadway.com)
- The nucleus is the most vital organelle within the cell. (farinelliandthekingbroadway.com)
- What is the least important organelle in a cell? (farinelliandthekingbroadway.com)
- The ribosome may be the smallest organelle in the cell, but it plays an important part. (farinelliandthekingbroadway.com)
- What Are The 12 Organelles In A Cell? (farinelliandthekingbroadway.com)
- What is the most useless cell organelle? (farinelliandthekingbroadway.com)
- The cell wall is an organelle that is present in plant, fungi, and bacterial cells. (farinelliandthekingbroadway.com)
- What organelle functions most like the brain of a cell? (farinelliandthekingbroadway.com)
- Name: Biology Date: Period: Cell Organelles Worksheet Complete the following table by writing the name of the cell part or organelle in the right hand column that matches the structure/function in the left hand column. (studyres.com)
- Each cell process is carried out in a specific location in the cell, often located in or around an organelle . (lumenlearning.com)
- Think of an organelle as a level of organization between macromolecules and the cell. (lumenlearning.com)
- Organelles carry out specialized tasks within the cell, localizing functions such as replication, energy production, protein synthesis, and processing of food and waste. (lumenlearning.com)
- The various cells differ in the arrangement and number of organelles, as well as structurally, giving rise to the hundreds of cell types found in the body. (lumenlearning.com)
- The focus of this section is to understand the organelles of the cell, how they interact with each other, and how they function during transport, growth and division in the cell. (lumenlearning.com)
- A cell is similar with each organelle serving a specific purpose. (lumenlearning.com)
- There are organelles whose job is to provide shape and structure to the cell, much like the city streets and bridges. (lumenlearning.com)
- Some of these actually move other organelles around the cell or change the shape of the cell. (lumenlearning.com)
- This organelle generates the ATP or energy for the cell. (lumenlearning.com)
- In other words, each cell has a true nucleus and membrane-bound organelles. (sciencenotes.org)
- Plastids are a group of plant cell organelles that perform a variety of essential functions. (sciencenotes.org)
- Each cell is composed of various organelles that are responsible for specific functions within the cell. (biochemden.com)
- In this article, we will explore the different cell organelles, their structures, and their functions. (biochemden.com)
- A cell organelle is a specialized structure within a cell that performs a specific function. (biochemden.com)
- The nucleus is a spherical or oval-shaped organelle that is usually located in the center of the cell. (biochemden.com)
- These organelles are known as the "powerhouses" of the cell because they are responsible for producing most of the energy that the cell needs to carry out its functions. (biochemden.com)
- What is Cell Organelle? (researchtweet.com)
- Any of the numerous cellular structures that perform a specific job inside a cell is referred to as an organelle. (researchtweet.com)
- A eukaryotic cell is defined by the presence of membrane-bound organelles, whereas a prokaryotic cell is defined by the absence of such organelles. (researchtweet.com)
- An organelle, by definition, is a membrane-bound compartment or structure in a cell that serves a specific purpose. (researchtweet.com)
- The living components inside the cell are known as organelles. (researchtweet.com)
- Not all of these organelles, however, are located in a single cell or organism. (researchtweet.com)
- An organelle is a specialised component of a cell that has a defined purpose. (researchtweet.com)
- Some of these parts, called organelles, are specialized structures that perform certain tasks within the cell. (medlineplus.gov)
- This organelle helps process molecules created by the cell. (medlineplus.gov)
- are complex organelles that convert energy from food into a form that the cell can use. (medlineplus.gov)
Cytoplasmic5
- I conclude that the role of Myt1 during pre-meiotic G2 phase arrest of male meiosis is to regulate discrete checkpoint mechanisms that are used to spatially and temporally coordinate cytoplasmic organelle behavior with the nuclear events of meiotic progression that are triggered by Cdc25Twe-mediated Cdk1 activation, at G2/MI. (ualberta.ca)
- Eukaryotic cells and prokaryotic cells are distinguished by the presence of cytoplasmic membrane-bound organelles. (researchtweet.com)
- Some sources classify single-membraned cytoplasmic structures such as lysosomes, endosomes, and vacuoles as organelles. (researchtweet.com)
- Similarly, because they are single-membrane confined cytoplasmic structures, lysosomes and vacuoles do not qualify as organelles. (researchtweet.com)
- Organelles may be divided into two categories: membrane-bound organelles (which include both double-membraned and single-membraned cytoplasmic structures) and non-membrane-bound organelles (also referred to as biomolecular complexes or proteinaceous organelles). (researchtweet.com)
Structures4
- The name organelle comes from the idea that these structures are parts of cells, as organs are to the body, hence organelle, the suffix -elle being a diminutive. (wikipedia.org)
- The first, broader conception of organelles is that they are membrane-bound structures. (wikipedia.org)
- Membrane-bound organelles are cellular structures that have a biological membrane that binds them together. (researchtweet.com)
- RESUME L'hématoxyline et l'éosine sont les colorations les plus couramment utilisées dans les laboratoires de pathologie pour la mise en évidence des structures cellulaires. (who.int)
Contain a nucleus1
- Plant cells, like all eukaryotic cells, contain a nucleus and other organelles, each with its distinct functions. (sciencenotes.org)
Subunit1
- consists of two subunits a large subunit and a small subunit not a membrane-bound organelle. (farinelliandthekingbroadway.com)
Prokaryotic1
- Prokaryotic cells, such as bacteria, do not have membrane-bound organelles. (biochemden.com)
Double membrane1
- This is actually a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm. (pressbooks.pub)
Cell's organelles2
- Optimized tweezers enable precise 3-D manipulations of a cell's organelles. (the-scientist.com)
- Arizona State University's "Ask a Biologist" provides a description and illustration of each of the cell's organelles . (medlineplus.gov)
Eukaryotic organelles1
- https://artscolumbia.org/of-eukaryotic-organelles-10-1-96-essay-67110/ [Accessed: 23 Sep. (artscolumbia.org)
Membraneless Organelles6
- Membraneless organelles appear highly sensitive to ion concentrations in their environment. (the-scientist.com)
- Infographic: What Are Membraneless Organelles? (the-scientist.com)
- What rules govern the structure of membraneless organelles? (buffalo.edu)
- A study published on Feb. 8 in Nature Communications explores how these compartments, also known as membraneless organelles (MLOs) or biomolecular condensates, form and organize themselves. (buffalo.edu)
- We found two different mechanisms that allowed us to control the architecture of synthetic membraneless organelles formed inside a test tube. (buffalo.edu)
- The Banerjee lab studies membraneless organelles. (buffalo.edu)
Cells21
- Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. (wikipedia.org)
- There are many types of organelles, particularly in eukaryotic cells. (wikipedia.org)
- Organ systems comprised of bits of tissue, formed by cells, made up of organelles , formed by carbon compounds. (dictionary.com)
- This 3D image of human breast cancer bone metastases shows the formation of the newly described organelle (magenta) in cancer cells (cyan). (princeton.edu)
- Each organelle marker plasmids are tested by transfection into HEK293 or SKOv3 cells followed by imaging via confocal microscopy. (origene.com)
- Cells contain an assortment of organelles which each have their own specialized role. (elifesciences.org)
- Asymmetric inheritance of organelle and cellular compounds between daughter cells impacts on the phenotypic variability and was found to be a hallmark for differentiation and rejuvenation in stem-like cells as much as a mechanism for enhancing resistance in bacteria populations. (biorxiv.org)
- Organelles play a critical role in cellular function, and the detection of specific organelles with organelle-selective stains, dyes, or specific antibodies is key in fluorescence imaging of cells and tissues. (thermofisher.com)
- Name the organelle of plant cells in which photosynthesis occurs. (tutorialspoint.com)
- Chloroplasts are the organelle of plant cells in which photosynthesis occurs. (tutorialspoint.com)
- Harvard University researchers have discovered a new organelle inside the gut cells of the fruit fly - a surprise discovery, staring us in the face, in one of the most well-studied animals in all of science. (freethink.com)
- Researchers have discovered a new organelle inside the gut cells of the fruit fly - a surprise in one of science's most studied models. (freethink.com)
- But despite how long we've studied cells - basically since the invention of the microscope - we continue to find new organelles, including one inside scent-sensing neurons discovered just this past winter . (freethink.com)
- Fittingly named a PXo body, the organelle then changed the phosphate into phospholipids, which cells use in membrane construction. (freethink.com)
- Correct positioning of organelles is essential to eukaryotic cells. (rupress.org)
- the most numerous organelles in most cells. (farinelliandthekingbroadway.com)
- These are unique organelles found in plant cells. (sciencenotes.org)
- The nucleus is a critical organelle that is present in most eukaryotic cells. (biochemden.com)
- Cells have small compartments often known as organelles that carry out advanced biochemical reactions. (myspaceastronomy.com)
- The researchers state that the know-how can be utilized to assemble synthetic organelles that may provide ATP or different helpful molecules to cells in broken or diseased tissues. (myspaceastronomy.com)
- It also provides a track-like system that directs the movement of organelles and other substances within cells. (medlineplus.gov)
Lysosomal1
- Defects in organelles from the lysosomal system may lead to HPS. (medscape.com)
Functions4
- The non-membrane bound organelles, also called large biomolecular complexes, are large assemblies of macromolecules that carry out particular and specialized functions, but they lack membrane boundaries. (wikipedia.org)
- Our strategy for optogenetic control of organelle positioning will be widely applicable to explore site-specific organelle functions in different model systems. (nature.com)
- The term "non-living" refers to the fact that the inclusions do not perform the biological functions that organelles do. (researchtweet.com)
- The nucleus is an organelle that regulates gene expression and is important for preserving DNA integrity as well as governing cellular functions such as metabolism, growth, and reproduction. (researchtweet.com)
Antibody1
- If you have an antibody specific for an organelle, you can also use that as a reference point. (origene.com)
Nucleus and other organelles1
- Experiments in C. elegans reveal new insights into how the ANC-1 protein helps to anchor the nucleus and other organelles in place. (elifesciences.org)
Organs2
- Organelle literally translates to "little organs. (researchtweet.com)
- In some ways, they are like a cell's organs (organelles). (msdmanuals.com)
Proteomics1
- Organelle Proteomics. (lu.se)
Cytoskeletal2
- Note that in most eukaryotes, organelles are moved around by cytoskeletal elements, microtubules and/or microfilaments. (asmblog.org)
- Instead, the phenotypic analysis of myt1 mutants indicated that Myt1 activity is required for structural integrity of a germline specific membranous cytoskeletal organelle called the fusome (or intercellular bridges). (ualberta.ca)
Myosin3
- Figure 2: Light-induced myosin-Vb recruitment anchors organelles or targets them into dendritic spines. (nature.com)
- Our study reveals a critical step in the spatial regulation of myosin V-dependent organelle transport and may reveal common mechanisms for how molecular motors accurately deposit cargoes at the correct locations. (rupress.org)
- Upon arrival at their correct locations, organelles detach from myosin V, thereby terminating transport. (rupress.org)
Biology1
- The latest breakthrough, featuring the as-yet unnamed organelle, adds new understanding to the role of the Wnt signaling pathway, a system whose discovery led to the 1995 Nobel Prize for Eric Wieschaus , Princeton's Squibb Professor in Molecular Biology and a professor in the Lewis-Sigler Institute for Integrative Genomics. (princeton.edu)
Spherical1
- It is a dense and spherical organelle. (farinelliandthekingbroadway.com)
Name organelle1
- The name organelle is derived from the New Latin organella, which is a diminutive of the Medieval Latin organum, which means "body organ. (researchtweet.com)
Entire organelle1
- Earlier studies revealed the individual components that make up the BMC shell, but imaging the entire organelle was challenging because of its large mass of about 6.5 megadaltons, roughly equivalent to the mass of 6.5 million hydrogen atoms. (sciencedaily.com)
Thought to lack organelles2
- Microbes, traditionally thought to lack organelles, get a metabolic boost from geometric compartments that act as cauldrons for chemical reactions. (the-scientist.com)
- Prokaryotes, which were previously thought to lack organelles, have lately been shown to have their own type of "organelle. (researchtweet.com)
Compartments1
- However, they are sometimes referred to as proteinaceous micro-compartments rather than genuine organelles in other sources. (researchtweet.com)
Bacterial4
- But more importantly, it provides the very first picture of the shell of an intact bacterial organelle membrane. (sciencedaily.com)
- Having the full structural view of the bacterial organelle membrane can help provide important information in fighting pathogens or bioengineering bacterial organelles for beneficial purposes. (sciencedaily.com)
- These organelles, or bacterial microcompartments (BMCs), are used by some bacteria to fix carbon dioxide, Kerfeld noted. (sciencedaily.com)
- Still, you get the idea that in this eu-karyote, with the smallest of all phototrophic genomes, organelle division is a reliable and well-regulated process coordinating components of bacterial as well as eukaryotic origin. (asmblog.org)
Spatially1
- Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). (wikipedia.org)
Microtubules2
- These protein rich organelles include intermediate filaments , microtubules , and microfilaments . (lumenlearning.com)
- One special organelle composed of microtubules is located in an area near the nucleus, the centrosome . (lumenlearning.com)
Compounds2
- This class of organelles also helps many types of pathogenic bacteria metabolize compounds that are not available to normal, non-pathogenic microbes, giving the pathogens a competitive advantage. (sciencedaily.com)
- The study authors said that by using the structural data from this paper, researchers can design experiments to study the mechanisms for how the molecules get across this protein membrane, and to build custom organelles for carbon capture or to produce valuable compounds. (sciencedaily.com)
Lipid2
- Lipid droplets are also clustered and the microtubule network is disrupted by the movement of the untethered organelles. (elifesciences.org)
- An organelle, according to some sources, is one that is surrounded by lipid bilayers. (researchtweet.com)
Specific2
- At the epicenter of this immune and metabolic reprogramming ( immunometabolism ) are organelles that compartmentalize specific metabolic reactions. (georgetown.edu)
- In a broader sense, an organelle is any cellular structure that performs a specific function, whether or not it is membrane-bound. (researchtweet.com)
Protein1
- Two critical factors during this dauntingly complex process appear to be the establishment of metabolic connectivity between the symbiotic partners, and the evolution of nuclear control over protein expression levels within the organelle. (frontiersin.org)
Plastids1
- The cercozoan amoeba Paulinella chromatophora contains photosynthetic organelles-termed chromatophores-that evolved from a cyanobacterium ∼100 million years ago, independently from plastids in plants and algae. (frontiersin.org)
Carbon1
- Which eukaryotic organelle is responsible for making carbon dioxide? (answers.com)
Metabolic1
- Obesity-driven organelle stress is associated with an unresolving, low-grade inflammation (also known as metaflammation due to its metabolic origin). (georgetown.edu)
Pathways2
- Molecular motors transport organelles to their proper destinations, yet little is known about the pathways that define these destinations. (rupress.org)
- Melanosomes and other lysosome-related organelles obtain cargoes from early endosomes, but the fusion machinery involved and its recycling pathways are unknown. (medscape.com)
Morphology1
- First, the amount of RNA in the mixture helps to regulate the morphology of the organelles. (buffalo.edu)
Melanosomes1
- This process takes place in special organelles called melanosomes. (medscape.com)
Metabolism1
- Theme 1 - The interface of organelle signalling and metabolism. (edu.au)
Search1
- The discovery may spark a search for phosphate-storing organelles in other animals - including humans. (freethink.com)
Markers3
- All organelle markers are cloned into the SgfI and MluI sites. (origene.com)
- All organelle markers can be easily shuttled among any of the Destination vectors using the PrecisonShuttle system. (origene.com)
- 1. Light microscopy using phosphatases as organelle markers. (moredun.org.uk)
Consists1
- The ribosome-associated organelle consists of tightly packed tubes, not flat sheets as previously believed, according to new super-resolution microscopy images. (the-scientist.com)
20191
- Princeton cancer researchers Yibin Kang (left) and Mark Esposito, seen here in April 2019, discovered a new, still-unnamed organelle that plays a role in bone metastasis and is formed via liquid-liquid phase separation - when liquid blobs of living materials merge into each other. (princeton.edu)