The origin of life. It includes studies of the potential basis for life in organic compounds but excludes studies of the development of altered forms of life through mutation and natural selection, which is BIOLOGICAL EVOLUTION.
The cellular processes involved in adjustments to the MITOCHONDRIAL VOLUME, content, and activity, that depend on the energy demands of the cell.
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
An endoribonuclease that is specific for double-stranded RNA. It plays a role in POST-TRANSCRIPTIONAL RNA PROCESSING of pre-RIBOSOMAL RNA and a variety of other RNA structures that contain double-stranded regions.
Proteins encoded by the mitochondrial genome or proteins encoded by the nuclear genome that are imported to and resident in the MITOCHONDRIA.
Microbodies which occur in animal and plant cells and in certain fungi and protozoa. They contain peroxidase, catalase, and allied enzymes. (From Singleton and Sainsbury, Dictionary of Microbiology and Molecular Biology, 2nd ed)
A transcription factor that controls the expression of variety of proteins including CYTOCHROME C and 5-AMINOLEVULINATE SYNTHETASE. It plays an important role in maintenance of the RESPIRATORY CHAIN of MITOCHONDRIA.
Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.
Within most types of eukaryotic CELL NUCLEUS, a distinct region, not delimited by a membrane, in which some species of rRNA (RNA, RIBOSOMAL) are synthesized and assembled into ribonucleoprotein subunits of ribosomes. In the nucleolus rRNA is transcribed from a nucleolar organizer, i.e., a group of tandemly repeated chromosomal genes which encode rRNA and which are transcribed by RNA polymerase I. (Singleton & Sainsbury, Dictionary of Microbiology & Molecular Biology, 2d ed)
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
Post-transcriptional biological modification of messenger, transfer, or ribosomal RNAs or their precursors. It includes cleavage, methylation, thiolation, isopentenylation, pseudouridine formation, conformational changes, and association with ribosomal protein.
A heterogeneous group of inherited metabolic disorders marked by absent or dysfunctional PEROXISOMES. Peroxisomal enzymatic abnormalities may be single or multiple. Biosynthetic peroxisomal pathways are compromised, including the ability to synthesize ether lipids and to oxidize long-chain fatty acid precursors. Diseases in this category include ZELLWEGER SYNDROME; INFANTILE REFSUM DISEASE; rhizomelic chondrodysplasia (CHONDRODYSPLASIA PUNCTATA, RHIZOMELIC); hyperpipecolic acidemia; neonatal adrenoleukodystrophy; and ADRENOLEUKODYSTROPHY (X-linked). Neurologic dysfunction is a prominent feature of most peroxisomal disorders.
The large subunit of the 80s ribosome of eukaryotes. It is composed of the 28S RIBOSOMAL RNA, the 5.8S RIBOSOMAL RNA, the 5S RIBOSOMAL RNA, and about 50 different RIBOSOMAL PROTEINS.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Small double-stranded, non-protein coding RNAs, 21-25 nucleotides in length generated from single-stranded microRNA gene transcripts by the same RIBONUCLEASE III, Dicer, that produces small interfering RNAs (RNA, SMALL INTERFERING). They become part of the RNA-INDUCED SILENCING COMPLEX and repress the translation (TRANSLATION, GENETIC) of target RNA by binding to homologous 3'UTR region as an imperfect match. The small temporal RNAs (stRNAs), let-7 and lin-4, from C. elegans, are the first 2 miRNAs discovered, and are from a class of miRNAs involved in developmental timing.
The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)
A basic-leucine zipper transcription factor that is involved in regulating inflammatory responses, MORPHOGENESIS, and HEME biosynthesis.
Specific particles of membrane-bound organized living substances present in eukaryotic cells, such as the MITOCHONDRIA; the GOLGI APPARATUS; ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.
RNA transcripts of the DNA that are in some unfinished stage of post-transcriptional processing (RNA PROCESSING, POST-TRANSCRIPTIONAL) required for function. RNA precursors may undergo several steps of RNA SPLICING during which the phosphodiester bonds at exon-intron boundaries are cleaved and the introns are excised. Consequently a new bond is formed between the ends of the exons. Resulting mature RNAs can then be used; for example, mature mRNA (RNA, MESSENGER) is used as a template for protein production.
Syndrome characterized by the triad of oculocutaneous albinism (ALBINISM, OCULOCUTANEOUS); PLATELET STORAGE POOL DEFICIENCY; and lysosomal accumulation of ceroid lipofuscin.
Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.
Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.
Melanin-containing organelles found in melanocytes and melanophores.
Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.
A family of RNA-binding proteins that has specificity for MICRORNAS and SMALL INTERFERING RNA molecules. The proteins take part in RNA processing events as core components of RNA-induced silencing complex.
Thin, hairlike appendages, 1 to 20 microns in length and often occurring in large numbers, present on the cells of gram-negative bacteria, particularly Enterobacteriaceae and Neisseria. Unlike flagella, they do not possess motility, but being protein (pilin) in nature, they possess antigenic and hemagglutinating properties. They are of medical importance because some fimbriae mediate the attachment of bacteria to cells via adhesins (ADHESINS, BACTERIAL). Bacterial fimbriae refer to common pili, to be distinguished from the preferred use of "pili", which is confined to sex pili (PILI, SEX).
An autosomal recessive disorder due to defects in PEROXISOME biogenesis which involves more than 13 genes encoding peroxin proteins of the peroxisomal membrane and matrix. Zellweger syndrome is typically seen in the neonatal period with features such as dysmorphic skull; MUSCLE HYPOTONIA; SENSORINEURAL HEARING LOSS; visual compromise; SEIZURES; progressive degeneration of the KIDNEYS and the LIVER. Zellweger-like syndrome refers to phenotypes resembling the neonatal Zellweger syndrome but seen in children or adults with apparently intact peroxisome biogenesis.
A family of transcription factors that control expression of a variety of nuclear GENES encoding proteins that function in the RESPIRATORY CHAIN of the MITOCHONDRIA.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
A gene silencing phenomenon whereby specific dsRNAs (RNA, DOUBLE-STRANDED) trigger the degradation of homologous mRNA (RNA, MESSENGER). The specific dsRNAs are processed into SMALL INTERFERING RNA (siRNA) which serves as a guide for cleavage of the homologous mRNA in the RNA-INDUCED SILENCING COMPLEX. DNA METHYLATION may also be triggered during this process.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.
A family of cellular proteins that mediate the correct assembly or disassembly of polypeptides and their associated ligands. Although they take part in the assembly process, molecular chaperones are not components of the final structures.
Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)
Proteins that are structural components of bacterial fimbriae (FIMBRIAE, BACTERIAL) or sex pili (PILI, SEX).
A large family of RNA helicases that share a common protein motif with the single letter amino acid sequence D-E-A-D (Asp-Glu-Ala-Asp). In addition to RNA helicase activity, members of the DEAD-box family participate in other aspects of RNA metabolism and regulation of RNA function.
A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.
Proteins found in any species of bacterium.
Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.
A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.
Plant cell inclusion bodies that contain the photosynthetic pigment CHLOROPHYLL, which is associated with the membrane of THYLAKOIDS. Chloroplasts occur in cells of leaves and young stems of plants. They are also found in some forms of PHYTOPLANKTON such as HAPTOPHYTA; DINOFLAGELLATES; DIATOMS; and CRYPTOPHYTA.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Highly conserved nuclear RNA-protein complexes that function in RNA processing in the nucleus, including pre-mRNA splicing and pre-mRNA 3'-end processing in the nucleoplasm, and pre-rRNA processing in the nucleolus (see RIBONUCLEOPROTEINS, SMALL NUCLEOLAR).
A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
Membrane-bound cytoplasmic vesicles formed by invagination of phagocytized material. They fuse with lysosomes to form phagolysosomes in which the hydrolytic enzymes of the lysosome digest the phagocytized material.
The quantity of volume or surface area of ORGANELLES.
The small subunit of the 80s ribosome of eukaryotes. It is composed of the 18S RIBOSOMAL RNA and 32 different RIBOSOMAL PROTEINS.
Transport proteins that carry specific substances in the blood or across cell membranes.
Nucleolar RNA-protein complexes that function in pre-ribosomal RNA processing.
A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.
Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.
Constituent of the 40S subunit of eukaryotic ribosomes. 18S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.
Proteins found in any species of fungus.
The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.
A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Proteins obtained from ESCHERICHIA COLI.
A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.
Established cell cultures that have the potential to propagate indefinitely.
Small nuclear RNAs that are involved in the processing of pre-ribosomal RNA in the nucleolus. Box C/D containing snoRNAs (U14, U15, U16, U20, U21 and U24-U63) direct site-specific methylation of various ribose moieties. Box H/ACA containing snoRNAs (E2, E3, U19, U23, and U64-U72) direct the conversion of specific uridines to pseudouridine. Site-specific cleavages resulting in the mature ribosomal RNAs are directed by snoRNAs U3, U8, U14, U22 and the snoRNA components of RNase MRP and RNase P.
The quantity of volume or surface area of MITOCHONDRIA.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.
Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.
Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.
Endosomes containing intraluminal vesicles which are formed by the inward budding of the endosome membrane. Multivesicular bodies (MVBs) may fuse with other organelles such as LYSOSOMES or fuse back with the PLASMA MEMBRANE releasing their contents by EXOCYTOSIS. The MVB intraluminal vesicles released into the extracellular environment are known as EXOSOMES.
A distinct subnuclear domain enriched in splicesomal snRNPs (RIBONUCLEOPROTEINS, SMALL NUCLEAR) and p80-coilin.
The two lipoprotein layers in the MITOCHONDRION. The outer membrane encloses the entire mitochondrion and contains channels with TRANSPORT PROTEINS to move molecules and ions in and out of the organelle. The inner membrane folds into cristae and contains many ENZYMES important to cell METABOLISM and energy production (MITOCHONDRIAL ATP SYNTHASE).
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.
Macromolecular complexes formed from the association of defined protein subunits.
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
The metabolic process of all living cells (animal and plant) in which oxygen is used to provide a source of energy for the cell.
Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Ribonucleic acid in fungi having regulatory and catalytic roles as well as involvement in protein synthesis.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.
Vesicles derived from the GOLGI APPARATUS containing material to be released at the cell surface.
Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.
Single chains of amino acids that are the units of multimeric PROTEINS. Multimeric proteins can be composed of identical or non-identical subunits. One or more monomeric subunits may compose a protomer which itself is a subunit structure of a larger assembly.
A broad category of proteins involved in the formation, transport and dissolution of TRANSPORT VESICLES. They play a role in the intracellular transport of molecules contained within membrane vesicles. Vesicular transport proteins are distinguished from MEMBRANE TRANSPORT PROTEINS, which move molecules across membranes, by the mode in which the molecules are transported.
Membranous cisternae of the CHLOROPLAST containing photosynthetic pigments, reaction centers, and the electron-transport chain. Each thylakoid consists of a flattened sac of membrane enclosing a narrow intra-thylakoid space (Lackie and Dow, Dictionary of Cell Biology, 2nd ed). Individual thylakoids are interconnected and tend to stack to form aggregates called grana. They are found in cyanobacteria and all plants.
The two dissimilar sized ribonucleoprotein complexes that comprise a RIBOSOME - the large ribosomal subunit and the small ribosomal subunit. The eukaryotic 80S ribosome is composed of a 60S large subunit and a 40S small subunit. The bacterial 70S ribosome is composed of a 50S large subunit and a 30S small subunit.
The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Vesicles that are involved in shuttling cargo from the interior of the cell to the cell surface, from the cell surface to the interior, across the cell or around the cell to various locations.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in fungi.
The process of moving specific RNA molecules from one cellular compartment or region to another by various sorting and transport mechanisms.
The small subunit of eubacterial RIBOSOMES. It is composed of the 16S RIBOSOMAL RNA and about 23 different RIBOSOMAL PROTEINS.
Proteins involved in the transport of specific substances across the membranes of the MITOCHONDRIA.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
The segregation and degradation of damaged or unwanted cytoplasmic constituents by autophagic vacuoles (cytolysosomes) composed of LYSOSOMES containing cellular components in the process of digestion; it plays an important role in BIOLOGICAL METAMORPHOSIS of amphibians, in the removal of bone by osteoclasts, and in the degradation of normal cell components in nutritional deficiency states.
Electron transfer through the cytochrome system liberating free energy which is transformed into high-energy phosphate bonds.
A family of proteins that promote unwinding of RNA during splicing and translation.
The small ribonucleoprotein component of RIBOSOMES. It contains the MESSENGER RNA binding site and two TRANSFER RNA binding sites - one for the incoming AMINO ACYL TRNA (A site) and the other (P site) for the peptidyl tRNA carrying the elongating peptide chain.
An adaptor protein complex found primarily on perinuclear compartments.
A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
A family of MEMBRANE TRANSPORT PROTEINS that require ATP hydrolysis for the transport of substrates across membranes. The protein family derives its name from the ATP-binding domain found on the protein.
Filamentous or elongated proteinaceous structures which extend from the cell surface in gram-negative bacteria that contain certain types of conjugative plasmid. These pili are the organs associated with genetic transfer and have essential roles in conjugation. Normally, only one or a few pili occur on a given donor cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed, p675) This preferred use of "pili" refers to the sexual appendage, to be distinguished from bacterial fimbriae (FIMBRIAE, BACTERIAL), also known as common pili, which are usually concerned with adhesion.
Membrane-limited structures derived from the plasma membrane or various intracellular membranes which function in storage, transport or metabolism.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
A large family of MONOMERIC GTP-BINDING PROTEINS that play a key role in cellular secretory and endocytic pathways. EC 3.6.1.-.
A sirtuin family member found primarily in the CELL NUCLEUS. It is an NAD-dependent deacetylase with specificity towards HISTONES and a variety of proteins involved in gene regulation.
Enzymes that catalyze the cleavage of a carbon-sulfur bond by means other than hydrolysis or oxidation. EC 4.4.
Constituent of the 60S subunit of eukaryotic ribosomes. 5.8S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.
Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
Proteins isolated from the outer membrane of Gram-negative bacteria.
A sequence of amino acids in a polypeptide or of nucleotides in DNA or RNA that is similar across multiple species. A known set of conserved sequences is represented by a CONSENSUS SEQUENCE. AMINO ACID MOTIFS are often composed of conserved sequences.
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.
A complex of proteins that assemble the SNRNP CORE PROTEINS into a core structure that surrounds a highly conserved RNA sequence found in SMALL NUCLEAR RNA. They are found localized in the GEMINI OF COILED BODIES and in the CYTOPLASM. The SMN complex is named after the Survival of Motor Neuron Complex Protein 1, which is a critical component of the complex.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Self-replicating cytoplasmic organelles of plant and algal cells that contain pigments and may synthesize and accumulate various substances. PLASTID GENOMES are used in phylogenetic studies.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Genes that are located on the MITOCHONDRIAL DNA. Mitochondrial inheritance is often referred to as maternal inheritance but should be differentiated from maternal inheritance that is transmitted chromosomally.
Screening techniques first developed in yeast to identify genes encoding interacting proteins. Variations are used to evaluate interplay between proteins and other molecules. Two-hybrid techniques refer to analysis for protein-protein interactions, one-hybrid for DNA-protein interactions, three-hybrid interactions for RNA-protein interactions or ligand-based interactions. Reverse n-hybrid techniques refer to analysis for mutations or other small molecules that dissociate known interactions.
Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.
The functional hereditary units of FUNGI.
Yeast-like ascomycetous fungi of the family Saccharomycetaceae, order SACCHAROMYCETALES isolated from exuded tree sap.
A whiplike motility appendage present on the surface cells. Prokaryote flagella are composed of a protein called FLAGELLIN. Bacteria can have a single flagellum, a tuft at one pole, or multiple flagella covering the entire surface. In eukaryotes, flagella are threadlike protoplasmic extensions used to propel flagellates and sperm. Flagella have the same basic structure as CILIA but are longer in proportion to the cell bearing them and present in much smaller numbers. (From King & Stansfield, A Dictionary of Genetics, 4th ed)
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
The aggregation of soluble ANTIGENS with ANTIBODIES, alone or with antibody binding factors such as ANTI-ANTIBODIES or STAPHYLOCOCCAL PROTEIN A, into complexes large enough to fall out of solution.
Gated transport mechanisms by which proteins or RNA are moved across the NUCLEAR MEMBRANE.
Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.
A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.
Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Proton-translocating ATPases responsible for ADENOSINE TRIPHOSPHATE synthesis in the MITOCHONDRIA. They derive energy from the respiratory chain-driven reactions that develop high concentrations of protons within the intermembranous space of the mitochondria.
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.
The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.
The chemical reactions involved in the production and utilization of various forms of energy in cells.
Interruption or suppression of the expression of a gene at transcriptional or translational levels.
A subclass of enzymes of the transferase class that catalyze the transfer of a methyl group from one compound to another. (Dorland, 28th ed) EC 2.1.1.
Complexes of RNA-binding proteins with ribonucleic acids (RNA).
A partitioning within cells due to the selectively permeable membranes which enclose each of the separate parts, e.g., mitochondria, lysosomes, etc.
A network of membrane compartments, located at the cytoplasmic side of the GOLGI APPARATUS, where proteins and lipids are sorted for transport to various locations in the cell or cell membrane.
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
Enzyme that catalyzes the first step of the tricarboxylic acid cycle (CITRIC ACID CYCLE). It catalyzes the reaction of oxaloacetate and acetyl CoA to form citrate and coenzyme A. This enzyme was formerly listed as EC
The space between the inner and outer membranes of a cell that is shared with the cell wall.
Proteins that originate from insect species belonging to the genus DROSOPHILA. The proteins from the most intensely studied species of Drosophila, DROSOPHILA MELANOGASTER, are the subject of much interest in the area of MORPHOGENESIS and development.
Proteins produced from GENES that have acquired MUTATIONS.
Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.
Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.
Self-replicating, short, fibrous, rod-shaped organelles. Each centriole is a short cylinder containing nine pairs of peripheral microtubules, arranged so as to form the wall of the cylinder.
The functional hereditary units of BACTERIA.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
Enzymes that hydrolyze GTP to GDP. EC 3.6.1.-.
A multicomponent, ribonucleoprotein complex comprised of one of the family of ARGONAUTE PROTEINS and the "guide strand" of the one of the 20- to 30-nucleotide small RNAs. RISC cleaves specific RNAs, which are targeted for degradation by homology to these small RNAs. Functions in regulating gene expression are determined by the specific argonaute protein and small RNA including siRNA (RNA, SMALL INTERFERING), miRNA (MICRORNA), or piRNA (PIWI-INTERACTING RNA).
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
The mitochondria of the myocardium.
Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)
A family of proteins involved in NUCLEOCYTOPLASMIC TRANSPORT. Karyopherins are heteromeric molecules composed two major types of components, ALPHA KARYOPHERINS and BETA KARYOPHERINS, that function together to transport molecules through the NUCLEAR PORE COMPLEX. Several other proteins such as RAN GTP BINDING PROTEIN and CELLULAR APOPTOSIS SUSCEPTIBILITY PROTEIN bind to karyopherins and participate in the transport process.
Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
Techniques to alter a gene sequence that result in an inactivated gene, or one in which the expression can be inactivated at a chosen time during development to study the loss of function of a gene.
A type of chromogranin which was first isolated from CHROMAFFIN CELLS of the ADRENAL MEDULLA but is also found in other tissues and in many species including human, bovine, rat, mouse, and others. It is an acidic protein with 431 to 445 amino acid residues. It contains fragments that inhibit vasoconstriction or release of hormones and neurotransmitter, while other fragments exert antimicrobial actions.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A complex of enzymes and PROTON PUMPS located on the inner membrane of the MITOCHONDRIA and in bacterial membranes. The protein complex provides energy in the form of an electrochemical gradient, which may be used by either MITOCHONDRIAL PROTON-TRANSLOCATING ATPASES or BACTERIAL PROTON-TRANSLOCATING ATPASES.
A multiribosomal structure representing a linear array of RIBOSOMES held together by messenger RNA; (RNA, MESSENGER); They represent the active complexes in cellular protein synthesis and are able to incorporate amino acids into polypeptides both in vivo and in vitro. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Cells of the higher organisms, containing a true nucleus bounded by a nuclear membrane.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Diseases caused by abnormal function of the MITOCHONDRIA. They may be caused by mutations, acquired or inherited, in mitochondrial DNA or in nuclear genes that code for mitochondrial components. They may also be the result of acquired mitochondria dysfunction due to adverse effects of drugs, infections, or other environmental causes.
The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Intracellular signaling protein kinases that play a signaling role in the regulation of cellular energy metabolism. Their activity largely depends upon the concentration of cellular AMP which is increased under conditions of low energy or metabolic stress. AMP-activated protein kinases modify enzymes involved in LIPID METABOLISM, which in turn provide substrates needed to convert AMP into ATP.
The artificial induction of GENE SILENCING by the use of RNA INTERFERENCE to reduce the expression of a specific gene. It includes the use of DOUBLE-STRANDED RNA, such as SMALL INTERFERING RNA and RNA containing HAIRPIN LOOP SEQUENCE, and ANTI-SENSE OLIGONUCLEOTIDES.
The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)
Peptide initiation factors from eukaryotic organisms. Over twelve factors are involved in PEPTIDE CHAIN INITIATION, TRANSLATIONAL in eukaryotic cells. Many of these factors play a role in controlling the rate of MRNA TRANSLATION.
A family of enzymes that catalyze the endonucleolytic cleavage of RNA. It includes EC 3.1.26.-, EC 3.1.27.-, EC 3.1.30.-, and EC 3.1.31.-.
TRANSPORT VESICLES formed when cell-membrane coated pits (COATED PITS, CELL-MEMBRANE) invaginate and pinch off. The outer surface of these vesicles is covered with a lattice-like network of COP (coat protein complex) proteins, either COPI or COPII. COPI coated vesicles transport backwards from the cisternae of the GOLGI APPARATUS to the rough endoplasmic reticulum (ENDOPLASMIC RETICULUM, ROUGH), while COPII coated vesicles transport forward from the rough endoplasmic reticulum to the Golgi apparatus.
Short chains of RNA (100-300 nucleotides long) that are abundant in the nucleus and usually complexed with proteins in snRNPs (RIBONUCLEOPROTEINS, SMALL NUCLEAR). Many function in the processing of messenger RNA precursors. Others, the snoRNAs (RNA, SMALL NUCLEOLAR), are involved with the processing of ribosomal RNA precursors.
Proteins found in any species of protozoan.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
An enzyme that catalyzes the formation of acetoacetyl-CoA from two molecules of ACETYL COA. Some enzymes called thiolase or thiolase-I have referred to this activity or to the activity of ACETYL-COA C-ACYLTRANSFERASE.

UV irradiation of polycyclic aromatic hydrocarbons in ices: production of alcohols, quinones, and ethers. (1/385)

Polycyclic aromatic hydrocarbons (PAHs) in water ice were exposed to ultraviolet (UV) radiation under astrophysical conditions, and the products were analyzed by infrared spectroscopy and mass spectrometry. Peripheral carbon atoms were oxidized, producing aromatic alcohols, ketones, and ethers, and reduced, producing partially hydrogenated aromatic hydrocarbons, molecules that account for the interstellar 3.4-micrometer emission feature. These classes of compounds are all present in carbonaceous meteorites. Hydrogen and deuterium atoms exchange readily between the PAHs and the ice, which may explain the deuterium enrichments found in certain meteoritic molecules. This work has important implications for extraterrestrial organics in biogenesis.  (+info)

Divergence time estimates for the early history of animal phyla and the origin of plants, animals and fungi. (2/385)

In the past, molecular clocks have been used to estimate divergence times among animal phyla, but those time estimates have varied widely (1200-670 million years ago, Ma). In order to obtain time estimates that are more robust, we have analysed a larger number of genes for divergences among three well-represented animal phyla, and among plants, animals and fungi. The time estimate for the chordate-arthropod divergence, using 50 genes, is 993 +/- 46 Ma. Nematodes were found to have diverged from the lineage leading to arthropods and chordates at 1177 +/- 79 Ma. Phylogenetic analyses also show that a basal position of nematodes has strong support (p > 99%) and is not the result of rate biases. The three-way split (relationships unresolved) of plants, animals and fungi was estimated at 1576 +/- 88 Ma. By inference, the basal animal phyla (Porifera, Cnidaria, Ctenophora) diverged between about 1200-1500 Ma. This suggests that at least six animal phyla originated deep in the Precambrian, more than 400 million years earlier than their first appearance in the fossil record.  (+info)

Prebiotic cytosine synthesis: a critical analysis and implications for the origin of life. (3/385)

A number of theories propose that RNA, or an RNA-like substance, played a role in the origin of life. Usually, such hypotheses presume that the Watson-Crick bases were readily available on prebiotic Earth, for spontaneous incorporation into a replicator. Cytosine, however, has not been reported in analyses of meteorites nor is it among the products of electric spark discharge experiments. The reported prebiotic syntheses of cytosine involve the reaction of cyanoacetylene (or its hydrolysis product, cyanoacetaldehyde), with cyanate, cyanogen, or urea. These substances undergo side reactions with common nucleophiles that appear to proceed more rapidly than cytosine formation. To favor cytosine formation, reactant concentrations are required that are implausible in a natural setting. Furthermore, cytosine is consumed by deamination (the half-life for deamination at 25 degrees C is approximately 340 yr) and other reactions. No reactions have been described thus far that would produce cytosine, even in a specialized local setting, at a rate sufficient to compensate for its decomposition. On the basis of this evidence, it appears quite unlikely that cytosine played a role in the origin of life. Theories that involve replicators that function without the Watson-Crick pairs, or no replicator at all, remain as viable alternatives.  (+info)

Molecular evolution: aminoacyl-tRNA synthetases on the loose. (4/385)

Modified versions - paralogs - of the catalytic domain of at least three different aminoacyl-tRNA synthetases have been found to serve catalytic or regulatory roles in other reactions. These findings suggest that the first modern tRNA-synthetases could have been derived from amino-acid biosynthetic enzymes.  (+info)

Ribozymes--why so many, why so few? (5/385)

The RNA world scenario posits the existence of catalytic and genetic networks whose reactions are catalyzed by RNAs. Substantial progress has been made in recent years in the selection of RNA catalysts by SELEX, thus verifying one prediction of the model. However, many selected catalysts are long molecules, leading to a question of whether they could have been synthesized by a primitive replicator. It is proposed that the efficiency of some small ribozymes may have been augmented by other RNAs acting as transactivators.  (+info)

The evolution of a universal genetic code. (6/385)

Some of the basic problems presented by the rapid evolution of a universal genetic code can be resolved by a mechanism of co-evolution of the code and the amino acids it serves.  (+info)

Life: past, present and future. (7/385)

Molecular methods of taxonomy and phylogeny have changed the way in which life on earth is viewed; they have allowed us to transition from a eukaryote-centric (five-kingdoms) view of the planet to one that is peculiarly prokarote-centric, containing three kingdoms, two of which are prokaryotic unicells. These prokaryotes are distinguished from their eukaryotic counterparts by their toughness, tenacity and metabolic diversity. Realization of these features has, in many ways, changed the way we feel about life on earth, about the nature of life past and about the possibility of finding life elsewhere. In essence, the limits of life on this planet have expanded to such a degree that our thoughts of both past and future life have been altered. The abilities of prokaryotes to withstand many extreme conditions has led to the term extremophiles, used to describe the organisms that thrive under conditions thought just a few years ago, to be inconsistent with life. Perhaps the most extensive adaptation to extreme conditions, however, is represented by the ability of many bacteria to survive nutrient conditions not compatible with eukaryotic life. Prokaryotes have evolved to use nearly every redox couple that is in abundance on earth, filling the metabolic niches left behind by the oxygen-using, carbon-eating eukaryotes. This metabolic plasticity leads to a common feature in physically stratified environments of layered microbial communities, chemical indicators of the metabolic diversity of the prokaryotes. Such 'metabolic extremophily' forms a backdrop by which we can view the energy flow of life on this planet, think about what the evolutionary past of the planet might have been, and plan ways to look for life elsewhere, using the knowledge of energy flow on earth.  (+info)

The missing organic molecules on Mars. (8/385)

GC-MS on the Viking 1976 Mars missions did not detect organic molecules on the Martian surface, even those expected from meteorite bombardment. This result suggested that the Martian regolith might hold a potent oxidant that converts all organic molecules to carbon dioxide rapidly relative to the rate at which they arrive. This conclusion is influencing the design of Mars missions. We reexamine this conclusion in light of what is known about the oxidation of organic compounds generally and the nature of organics likely to come to Mars via meteorite. We conclude that nonvolatile salts of benzenecarboxylic acids, and perhaps oxalic and acetic acid, should be metastable intermediates of meteoritic organics under oxidizing conditions. Salts of these organic acids would have been largely invisible to GC-MS. Experiments show that one of these, benzenehexacarboxylic acid (mellitic acid), is generated by oxidation of organic matter known to come to Mars, is rather stable to further oxidation, and would not have been easily detected by the Viking experiments. Approximately 2 kg of meteorite-derived mellitic acid may have been generated per m(2) of Martian surface over 3 billion years. How much remains depends on decomposition rates under Martian conditions. As available data do not require that the surface of Mars be very strongly oxidizing, some organic molecules might be found near the surface of Mars, perhaps in amounts sufficient to be a resource. Missions should seek these and recognize that these complicate the search for organics from entirely hypothetical Martian life.  (+info)

Self-replication is any behavior of a dynamical system that yields construction of an identical copy of itself. Biological cells, given suitable environments, reproduce by cell division. During cell division, DNA is replicated and can be transmitted to offspring during reproduction. Biological viruses can replicate, but only by commandeering the reproductive machinery of cells through a process of infection. Harmful prion proteins can replicate by converting normal proteins into rogue forms. Computer viruses reproduce using the hardware and software already present on computers. Self-replication in robotics has been an area of research and a subject of interest in science fiction. Any self-replicating mechanism which does not make a perfect copy will experience genetic variation and will create variants of itself. These variants will be subject to natural selection, since some will be better at surviving in their current environment than others and will out-breed them. Early research by John von ...
All life on Earth uses three integrated molecular systems in which genetic information contained in DNA base sequences is transmitted to ribosomes by RNA and a genetic code, then translated into the amino acid sequences of structural and catalytic proteins. Therefore, the most important point for understanding the origin of life is to determine how such systems could emerge from random processes on the early Earth. In this review, two alternatives are compared: the RNA world hypothesis and the [GADV]-protein world hypothesis. [GADV] refers to four amino acids, Gly [G], Ala [A], Asp [D] and Val [V] that are conserved in the amino acid sequences of many common proteins. Here I will argue that the origins of the three primary processes required for life to begin can be better explained by the GADV hypothesis than the RNA world hypothesis. The GADV hypothesis also incorporates a conversion process by which random polymers can evolve into proteins with ordered sequences.
Molecular self-replication was almost certainly of central importance in the origin of life. Our lab was the first to experimentally demonstrate the feasibility of non-enzymatic peptide self-replication. We designed, synthesized, and characterized alpha-helical peptides that act autocatalytically in templating their own synthesis by accelerating the thioester-promoted amide-bond condensation of shorter fragments in neutral aqueous solution. The self-replication process displayed parabolic growth with the initial rates of product formation correlating with the square-root of initial template concentration. We further showed that this peptide self-replication process is chiroselective. The chiroselective amplication process discriminates between structures possessing even single stereochemical mutations within otherwise homochiral sequences. Moreover, the system exhibits a dynamic stereochemical `editing function; in contrast to the previously observed error correction, it makes use of ...
The discovery may also lead to new practical applications in chemistry and biology, but its main significance is that it addresses the age-old question of how life on Earth first arose. In particular, it paves the way for more extensive studies of how self-replicating DNA-RNA mixes could have evolved and spread on the primordial Earth and ultimately seeded the more mature biology of modern organisms.. This finding is an important step toward the development of a detailed chemical model of how the first life forms originated on Earth, says study senior author Ramanarayanan Krishnamurthy, PhD, associate professor of chemistry at Scripps Research.. The finding also nudges the field of origin-of-life chemistry away from the hypothesis that has dominated it in recent decades: The RNA World hypothesis posits that the first replicators were RNA-based, and that DNA arose only later as a product of RNA life forms.. Krishnamurthy and others have doubted the RNA World hypothesis in part because RNA ...
As promised, my penultimate note will be on the epistemological indistinguishability of the Copenhagen interpretation and the many worlds hypothesis. If youve stuck with me this far, but didnt understand that last sentence... well, you know what? Im willing to say that thats entirely my fault - Im trying to write this for the layman, after all. What I mean is that, if either the Copenhagen interpretation or the many worlds hypothesis was true, we could not tell the difference between them. The reason for this is that, under the many worlds hypothesis, we can only describe the future in terms of a probabilistic idea space (this is in fact what the many worlds hypothesis says reality is like). However, in hindsight, we will see only a series of quantum events that played out probabilistically. But under the Copenhagen interpretation, we can only describe the future in terms of probabilities, and if we were to fully describe all possible futures, this would be exactly the same as the many ... Compartmentalization is essential for the physico-chemical processes that underlie biological function---especially in multi-cellular organisms---and was arguably one of the critical steps in the prebiotic evolution of a proto-cell that led to the many life forms on Earth today. The cell itself is a compartment demarcated by a lipid membrane, so are certain organelles (little organs) such as the mitochondria and nuclei in our cells. There are, however, highly dynamic cellular compartments that are not bound by membranes. Examples include stress granules, germ granules, and the nucleolus. These bodies behave like mesoscopic liquid droplets, and are referred to as membraneless organelles, or biomolecular condensates in general. It has been discovered recently that they are often underpinned by reversible liquid-liquid phase separation of intrinsically disordered proteins (IDPs) and nucleic acids; and they stimulate and regulate ...
Changes in the equilibrium point of a reaction), other important features of life were not yet present. Step 5. During the next stage of prebiotic evolution, a variety of molecular additions resulted in increased stability of the primordial vesicles, which allowed them to withstand a wider range of physico-chemical stresses. Waterinsoluble surfactant precursors binding to the surface of micelles or vesicles may result in more complex systems (Luisi 2002). Peptides rich in helix motifs and large hydrophobic components analogous to terpenoids, kerogens or sterols could have contributed to early membranes. Although simple catalysts are thermodynamically more reliable, their catalytic performances are somewhat limited while their substrate specificity is rather low. Early life forms exclusively using such catalysts could not have reached satisfactory efficiency while competing with external processes. One must assume that during the early stages of life (the beginning of sequences 1 and 2 in Fig. ...
On todays ID the Future, host Eric Anderson sits down with Rob Stadler, co-author with Change Tan of The Stairway To Life: An Origin-Of-Life Reality Check. The topic of discussion-protocells. Stadler notes that the simplest existing single-celled organisms are far too sophisticated to have emerged through a blind process of prebiotic evolution. He further notes that this is widely acknowledged in the origin-of-life community, but those committed to a purely materialistic origin of the first life have a fallback explanation-protocells. That is, early biological structures far simpler than anything we find today. An intriguing hypothesis, but the problems with it, according to Stadler, are legion. Tune in as Stadler and Anderson walk through several lines of evidence that appear to Read More ›. ...
Autopoiesis is a term derived from Greek words, which means self-creation. It can be applied to evolution to describe the process undergone by inorganic molecules to form the building blocks of life. Biologically, it can be used to describe the eukaryotic cell, which produces more of itself through mitosis or meiosis. These are natural occurrences familiar to most of us on at least some level. Alternatively, self-replicating machines pioneered by scientists like John von Neumann can theoretically self-replicate, drawing from local resources to build more machines. These machines have been called clanking replicators, von Neumann machines, and universal constructors. Much of the premise of nanotechnology is based around self-replicating machines. The converse of autopoiesis is allopoiesis; current manufacturing techniques are allopoietic. Source: ...
These fragments could however be selected indirectZy by means of a specific probe that contains a selectable property, resistance to ampicillin (Ap), and that is incapable of self-replication. In vitro linkage of the probe fragment to a DNA fragment capable of self-replication leads to the formation of a replicon that can be selected in transformation. , 1978). , 1976). This was due to two features of the recombinant replicon: firstly, the inability of one replicon to function would not prevent perpetuation of the plasmid, and secondly, the two component replicons are dissimilar and the replication of each one could be individually inhibited (low levels of DNA polymerase I prevent replication of CoIE1; chloramphenicol treatment prevents the replication of pSC101). For this purpose we used ColE1 for cloning EcoRI-generated DNA fragments and pML21 for cloning HindIII-generated fragments (see Table 2). Table 7 lists the DNA fragments that were cloned and their phenotypes. A specific advantage of ...
A pre-cellular, virus-like stage of evolution appears to be, effectively, a logical inevitability. It is unimaginable that life started with large and complex genomes that were similar to those of archaea and bacteria, especially within the framework of the RNA world hypothesis, because large RNA genomes could not exist owing to RNA fragility. Thus, a pre-cellular stage of evolution must have involved genetic elements of virus-like size and complexity: the selfish replicons4,7. Importantly, unlike cellular life forms, viruses exploit different genome replication strategies, including those that were indispensable in the RNA world and during the transition to a DNA world, namely, RNA-dependent synthesis of RNA and DNA. The corresponding enzymes, the RNA-dependent RNA polymerases and reverse transcriptases, are bona fide VHGs that are shared by vast virus groups4. Conceivably, the diverse viral genomic strategies are relics of the primordial stage of evolution from which one strategy was ...
Life is widely believed to have evolved from a far simpler, self-replicating molecular system. However, the origin of the informational biopolymers (i.e. proteins, RNA, DNA) and the evolutionary path that led to early life remains obscure. The RNA world hypothesis posits that a hypothetical period once existed when information storage (genetics) and chemical catalysis (enzymatic activity) was once solely, or more heavily, the responsibility of RNA, before the advent of DNA and coded protein synthesis. A persistent challenge to this hypothesis is the lack of a plausible prebiotic pathway for the spontaneous formation of RNA polymers. We are investigating the possible origins of the chemical building blocks of RNA, and the hypothesis that RNA is largely the result of evolution - the descendant of an ancestral RNA-like polymer that had a different backbone and different nucleobases, a polymer that was much easier to assemble than present day RNA. As part of this research, we have demonstrated that ...
Scientists have been debating for decades the origin of life on earth. A number of hypotheses were proposed as to what emerged first RNA or DNA; with most scientists are in favour of the RNA World hypothesis. Assuming ...
How life came about from inanimate sets of chemicals is still a mystery. While we may never be certain which chemicals existed on prebiotic Earth, we can study the biomolecules we have today to give us clues about what happened ...
CSHL Press publishes monographs, technical manuals, handbooks, review volumes, conference proceedings, scholarly journals and videotapes. These examine important topics in molecular biology, genetics, development, virology, neurobiology, immunology and cancer biology. Manuscripts for books and for journal publication are invited from scientists world wide.
CSHL Press publishes monographs, technical manuals, handbooks, review volumes, conference proceedings, scholarly journals and videotapes. These examine important topics in molecular biology, genetics, development, virology, neurobiology, immunology and cancer biology. Manuscripts for books and for journal publication are invited from scientists world wide.
Ribozymes are currently a centerpiece in the ongoing debate on the origin of life. The ability of some RNA polymerizing ribozymes to synthesize functional products without the need for a DNA template[16] (they use an RNA template instead) makes RNA an attractive candidate for hypothetical primitive biochemistry. There is a growing body of chemical, molecular biological, and geological evidence which supports this hypothesis[17][18][19][20][21][22][23]. Additionally, the recent development of a self-replicating ribozyme derived from a viral ribozyme[24][25], demonstrates that self-replicating RNAs can exist. However, the evidence remains largely circumstantial as nothing conclusive has been found thus far and, even among biochemists, the hypothesis does have its detractors[26]. This hypothesis that life originated from RNA and ribonucleoprotein based biochemistry is called the RNA world hypothesis. It is considered by many biochemists to be the most plausible current hypothesis for the origin of ...
Simon George, leader of the organic geochemistry group in the Department of Earth and Planetary Sciences at Macquarie University in Sydney, Australia, argues that although the discovery of contamination was a setback for Brocks and others, it does not disprove the validity of all other findings based on samples of an apparently similar age. Jochen Brockss […] inference is that everybodys work is based on contamination. Hes certainly proven that some of the samples he worked on were affected by contamination, but its a bit of a leap to say everyone elses is, George explained. He argued that findings of steranes in ancient samples have been repeated in different geographical locations and by a variety of people at several leading institutions. Id be surprised if everyone was seeing contamination, he said.. Gordon Love, an organic geochemist at the University of California Riverside, CA, USA, is more cautious. He commented that findings based on archaean rocks are often unreliable ...
Much detail, indeed. We realize now that there is a mystery. The gap between non-living and living systems seems wider now that weve spent 60 years trying to bridge it. For comparison, the number of people playing with cellular automata is much smaller, but the self-replication problem has been solved handily in that context. Cellular automata are toy worlds that obey simple, made-up rules, for propagating from one generation to the next. The most famous is John Conways Game of Life, and here is a self-replicating pattern that works with those rules.. So Fact #1 would lead us to expect that maybe the first steps in the formation of life were easy and probable, while Fact #2 implies the opposite.. Fact #3 suggests maybe life appeared only once, adding more weight in favor of difficult and improbable. Or maybe life evolved in many places at many times, but one of these simply out-competed the others, and so descendents of just this one life remain on earth today. This is potentially the ...
Yes. I am arguing that no matter the complexity, self-replication, DNA codes, et cetera, life is exactly like thunder and volcanoes in terms of being natural phenomena that, because we dont know it all, are posited to be due to some anthropomorphic-but-magical being. So far we havent seen any magic involved in how life works, thus we have no reason to think that magic was ever involved, even if a problem like the origin of life is still in the works, even if it is not solved within my lifetime, I dont find the gods explanation satisfactory one bit. You do, perhaps, because you already know that theres gods. But I do not know such a thing. Thus, I see no reason to posit such a thing as explaining anything. Instead I see it as a god-of-the-gaps argument. I have to say I have very good reasons to see it that way. Unless you can show me that thunder, and volcanoes, and whatever other gods that you find superstitious are objectively different to the gods imagined by all the cultures that you ...
The replication mechanisms of living beings can be compared with the self-replication of automatons in the context of computability theory. In particular, DNA replication, analyzed from the perspective of the recursion theorem, indicates that its replication structure goes beyond biology and the quantum mechanisms that support it, as it is analyzed in the article Biology as an Axiomatic…
Bacteria are everywhere simply because they can colonize and adapt to different ecological niches in a very short-term period. One important molecular mechanism underlying the abilities of bacteria to colonize new niches is the acquisition of novel traits by conjugative DNA transfer. Under these circumstances, the so-called variable genome (as opposed to the core genome), which encodes an array of accessory functions (such as antibiotic resistance, specific degradation pathways, symbiosis, and virulence, to name a few), is freely exchanged among bacteria ( 1 ). These newly acquired DNA pieces are represented by intra- or extrachromosomal elements, which may or may not have self-replication and/or auto-transferable capacities. However, all of them participate in the fitness of the bacteria to colonize and to adapt to new niches; thus, they contribute to create new evolutionary patterns ( 2 ). Mobile genetic elements (MGEs) constitute a reservoir of DNA that is shared among bacterial species ( 3 ), and
First time accepted submitter mphall21 writes New York University scientists have developed artificial structures that can self-replicate, a process that has the potential to yield new types of materials. In the natural world, self-replication is ubiquitous in all living entities, but artificial se...
Viruses are the swarming bullies of biology, but it turns out their alarming self-replication could one day power your iPod. Weve seen them in batteries befo...
I can hardly convey the entire theory, and at an outline level it seems reasonable. But what was the force or principle that made the carbon compounds become more complex and self-organize into an RNA world with enzymes and coding / reproduction schemes? That remains a major question (but see the collection of RNA world references cited above). Energy alone, even when channeled in some approximation of the later major microbial metabolism to a profusion of organic molecules, does not, on the face of it, direct complexity or productive competition between mineral bubbles. (The authors have a later paper that claims that conditions forced life to emerge, but its details are not available, and the argument seems geochemical, not biological, so it does not seem to address the competitive issue.) We can refer to the anthropic principle to say that whatever led to us must have survived somehow, but that is a far weaker theory than one that drives events based on the chemistry of the time. So I think ...
I can hardly convey the entire theory, and at an outline level it seems reasonable. But what was the force or principle that made the carbon compounds become more complex and self-organize into an RNA world with enzymes and coding / reproduction schemes? That remains a major question (but see the collection of RNA world references cited above). Energy alone, even when channeled in some approximation of the later major microbial metabolism to a profusion of organic molecules, does not, on the face of it, direct complexity or productive competition between mineral bubbles. (The authors have a later paper that claims that conditions forced life to emerge, but its details are not available, and the argument seems geochemical, not biological, so it does not seem to address the competitive issue.) We can refer to the anthropic principle to say that whatever led to us must have survived somehow, but that is a far weaker theory than one that drives events based on the chemistry of the time. So I think ...
Over 99 per cent of organisms remain unknown to science - so could some of them sit outside the classic three domains of cellular life?
This short slide set relates the role of RNA in the processes of transcription and translation to RNAs evolutionary history and the remnants of the RNA world. Save the slide set to your computer to view the explanation and notes that go along with each slide.. Author/Source: ...
The origin of life on Earth is widely believed to have required the reactions of organic compounds and their self- and/or environmental organization. What those compounds were remains open to debate, as do the environment in and process or processes by which they became organized. Prebiotic chemistry is the systematic organized study of these phenomena. It is difficult to study poorly defined phenomena, and research has focused on producing compounds and structures familiar to contemporary biochemistry, which may or may not have been crucial for the origin of life. Given our ignorance, it may be instructive to explore the extreme regions of known and future investigations of prebiotic chemistry, where reactions fail, that will relate them to or exclude them from plausible environments where they could occur. Come critical parameters which most deserve investigation are discussed.
Science Assignment Help, Chemical evolution of spontaneous generation, Chemical Evolution The question of how life came into being in the first place still remained unanswered. To find an answer to this question means looking back billions of years in time and trying to imagine what the conditions on the earth co
Chemical reactions driven by the geological conditions on the early Earth might have led to the prebiotic evolution of self-replicating molecules. Scientists at Ludwig-Maximilians Universitaet (LMU) in Munich now report on a hydrothermal mechanism that could have promoted the process. Life is a product of evolution by natural selection. Thats…
Chemical Evolution. Carbohydrates and Lipids. Biochemistry. Systematic study of the molecular nature of life processes: the chemicals that make up of living systems (biochemicals), their organization into cells, and their chemical interactions Biochemicals have no life in themselves...
Phosphorus No Help for Chemical Evolution One of my favorite blues tunes is Born Under a Bad Sign, a song about someone who just cant catch a break. If there
4.2. The Halo The Galactic halo does not appear to suffer from a severe G-dwarf problem (Laird et al 1988, Pagel 1989, Beers et al 1992). The halo metallicity ranges from -4 dex to just below the solar value, with a mean of ~ -1.6 (Laird et al 1988, Hartwick 1976), Hartwick (1976) noted that this low metallicity suggested that either the halo yield was much lower than in the disk or that gas was removed from halo star formation (e.g. Ostriker & Thuan 1975). The favored model is that the halo lost its gas before chemical evolution could go to completion. Carney et al (1990), Wyse & Gilmore (1992) suggested that the missing spheroid mass fell to the center of the Galaxy and contributed most of the bulge mass, based on angular momentum considerations. Whether or not there is a minimum metallicity level, below which stars do not exist, has been debated for at least 20 years. Hartquist & Cameron (1977) predicted that there was an era of pregalactic nucleosynthesis by very massive zero metallicity ...
The central role that phosphates play in biological systems, suggests they also played an important role in the emergence of life on Earth. In recent years, numerous important advances have been made towards understanding the influence that phosphates may have had on prebiotic chemistry, and here, we highlight two important aspects of prebiotic phosphate chemistry. Firstly, we discuss prebiotic phosphorylation reactions; we specifically contrast aqueous electrophilic phosphorylation, and aqueous nucleophilic phosphorylation strategies, with dry-state phosphorylations that are mediated by dissociative phosphoryl-transfer. Secondly, we discuss the non-structural roles that phosphates can play in prebiotic chemistry. Here, we focus on the mechanisms by which phosphate has guided prebiotic reactivity through catalysis or buffering effects, to facilitating selective transformations in neutral water. Several prebiotic routes towards the synthesis of nucleotides, amino acids, and core metabolites, that have
The RNA world hypothesis is supported by RNAs ability to store, transmit, and duplicate genetic information, as DNA does. RNA can act as a ribozyme, a special type of enzyme. Because it can perform the tasks of both DNA and enzymes, RNA is believed to have once been capable of supporting independent life forms.[15] Some viruses use RNA as their genetic material, rather than DNA.[45] Further, while nucleotides were not found in experiments based on Miller-Urey experiment, their formation in prebiotically plausible conditions was reported in 2009;[22] the purine base known as adenine is merely a pentamer of hydrogen cyanide. Experiments with basic ribozymes, like Bacteriophage Qβ RNA, have shown that simple self-replicating RNA structures can withstand even strong selective pressures (e.g., opposite-chirality chain terminators).[46] Since there were no known chemical pathways for the abiogenic synthesis of nucleotides from pyrimidine nucleobases cytosine and uracil under prebiotic conditions, it ...
Our research objective is to understand and model the chemical processes on the primitive Earth that generated the first autocatalytic molecules and microstructures involved in the origin of life. Our approach involves (a) investigation of a model origin-of-life process named the Sugar Model that is based on the reaction of formaldehyde-derived sugars with ammonia and amines, and (b) elucidation of the constraints imposed on the chemistry of the origin of life by the fixed energies and rates of aliphatic organic reactions under mild aqueous conditions. The Sugar Model is a plausible one-pot prebiotic process that converts very simple substrates (formaldehyde, glycolaldehyde, ammonia, and hydrogen sulfide) to a variety of products: small catalytic molecules, energy-rich thioesters and phosphoanhydrides. More recently we showed (a) that homochiral amines (like amino acids and peptides) catalyze the stereoselective synthesis of tetrose sugars from glycolaldehyde, and (b) that sugar-amine (or ...
Lifes origin requires a molecule that can both store information and catalyze the synthesis of other molecules. RNA can catalyze simple reactions and can help as a template for protein synthesis and for more RNA synthesis. This suggests that RNA was probably the first genetic molecule to start life. Later we suspect that DNA evolved to be a more stable molecule, and proteins evolved to be more efficient enzymes. RNA with catalytic activity is referred to as ribozyme ...
The free nucleobases and mononucleotides of RNA do not form Watson-Crick base pairs in water, a fact that presents several challenges for the prebiotic synthesis of RNA. 2,6-Diaminopurine and adenosine-5′-monophosphate (AMP) are shown to form supramolecular assemblies with cyanuric acid in water. These assem Prebiotic chemistry and the molecular origins of life
As I understand it, plasmids, like mitochondria, have their own genetic material and are capable of self-replication. According to Wikipedia: Plasmids are considered replicons, units of DNA capable of replicating autonomously within a suitable host. However, like viruses, they are not classified as life. Plasmids are transmitted from one bacterium to another through conjugation. Unlike viruses, plasmids are naked DNA. However, some classes of plasmids encode the conjugative sex pilus necessary for their own transfer. My understanding of that is that a bacteria gets their plasmids not because of the replication of their circular chromosome, nor because that chromosome have genes to code for the plasmid (I dont really know if thats possible), but because of the self-replication of their own plasmids. So, my question is how the first plasmid got into the first bacteria, if they are not in their chromosomes? Were they a virus other prokaryotic cell that had circular DNA, and got phagocytosed ...
As the cellular physiology is the outcome of enzymatic activity, so the enzymes must have developed before the cells. Gradually the gene aggregates became surrounded by a complex system of enzymes which formed the cytoplasm. These enzymes could have combined the nitrogen bases, simple sugars and phosphates into the nucleotides. Nucleotides might have combined to form nucleic acid which appear to be the biomolecules fulfilling the condition of supply of replicators in the origin of life. Presently the molecular biology operates on the principle of central dogma which states that flow of genetic informations is unidirectional and is shown as below: DNA (Transcription) → RNA (Translation) → Protein (With genetic informations) (With genetic message) This mechanism probably evolved from much simpler mechanism. Nucleic acid and proteins (enzymes) are two interdependent biomolecules. Proteins are synthesized by a process that begins with the transcription of informations from DNA to mRNA followed ...
Evolution and Biodiversity, Biological evolution, or evolution is the change in a populations genetic makeup through successive generations., While the Earth itself may be a billion years old, modern humans didnt exist until only 65 million years ago., After this chemical evolution had formed cells, biological evolution took place, creating single-celled prokayotic bacteria into single-celled eukayotic cells., Evidence indicates that Earths life is the result of around 1 billion years of chemical evolution to form the first cells., Origin of Earth, Natural Selection, occurs when some individuals of a population have genetically based traits that increase their chance of survival., If the trait helps the individual significantly, than chances are the rest of the population will develop these characteristics, Adaptive traits are any heritable trait that enables organisms to better survive., In all communities, species all have ecological niches. These are the species role in their environment/community
In the first paper we showed that you can create tension between a chemical and physical system to give rise to more complex systems. And in the second paper, we showed that these complex systems can have remarkable and unexpected functions, says David Lynn, a systems chemist in Emorys Department of Chemistry who led the research. The work was inspired by our current understanding of Darwinian selection of protein misfolding in neurodegenerative diseases ...
In the first paper we showed that you can create tension between a chemical and physical system to give rise to more complex systems. And in the second paper, we showed that these complex systems can have remarkable and unexpected functions, says David Lynn, a systems chemist in Emorys Department of Chemistry who led the research. The work was inspired by our current understanding of Darwinian selection of protein misfolding in neurodegenerative diseases ...
Principal Investigator:OZAWA Kazuhito, Project Period (FY):2009 - 2011, Research Category:Grant-in-Aid for Scientific Research (B), Section:一般, Research Field:Petrology/Mineralogy/Science of ore deposit
Newly formed protocell. Image 2 of 5. Artwork showing cellular components inside a basic cell membrane. This protocell (artificial cell) was formed from a synthetic primeval soup containing PNA (peptide nucleic acid, orange), fatty acids (blue) and lysosomes (enzyme-producing organelles, yellow). The primeval soup was a mix of carbon based molecules that chemically evolved to form simple cells, at the beginning of life. Scientists at Los Alamos National Laboratory in New Mexico, USA, attempted to recreate this in 2006 by making protocells. Here, the loose components have arranged themselves into an ordered structure resembling a simple cell. See G200/112-G200/116 for a series of images showing the creation of a protocell. - Stock Image G200/0113
The PAH World is a novel chemical structural model for the plausible formation of oligomeric proto-informational templating materials on the early Earth; presumably progenitors of the widely expected RNA World in chemical evolution theory. The model is based on the self-assembling discotic mesogenic behaviors of polynuclear aromatic compounds, their photochemical edge-derivatizations, and the selectivity of such stacked supramolecular aromatic core scaffolds for the edge-on binding and ~ 0.34 nm plane-parallel spacing of essentially random collections of small prebiotic heterocycles, taken up and concentrated directly from the presumed and surrounding dilute primordial soup. The constrained inter-base separation distance would select for oligomerizing linkers of fairly specific size, such as small methanal oligomers, which would also be taken up from the prebiotic chemical environment, condensing with the small heterocycles and also with each other to form the flexible structural ...
A simple mechanism could underlie the growth and self-replication of protocells-;putative ancestors of modern living cells-;suggests a study publishing September 3 in Biophysical Journal.
Scientists suggest a new way to study how biomolecules and minerals combined in Earths primordial soup.Provided by the Carnegie Institution, Washington, D.C.
This research shows how some of the basic building blocks of life could have been naturally occuring in an early Earth like environment. ...
Earths origin and evolution, isotope and trace element geochemistry, the role of crust and lithospheric mantle recycling in the generation of mantle chemical heterogeneity, the origin and distribution of water and other volatile elements in the Earths interior, and the thermal and chemical evolution of the Earths core and core/mantle ...
For cellular organisms, the transport of specific molecules across compartmentalizing membrane barriers is essential in order to exchange content with their environment and with other individuals. For example, content exchange between individuals enables horizontal gene transfer, an important factor in the evolution of cellular life.[30] While modern cells can rely on complicated protein machineries to catalyze these crucial processes, protocells must have accomplished this using more simple mechanisms. Protocells composed of fatty acids[31] would have been able to easily exchange small molecules and ions with their environment.[1] Membranes consisting of fatty acids have a relatively high permeability to molecules such as nucleoside monophosphate (NMP), nucleoside diphosphate (NDP), and nucleoside triphosphate (NTP), and may withstand millimolar concentrations of Mg2+.[32] Osmotic pressure can also play a significant role regarding this passive membrane transport.[1] Environmental effects have ...
We report the design, synthesis, and assembly of the 1.08-mega-base pair Mycoplasma mycoides JCVI-syn1.0 genome starting from digitized genome sequence information and its transplantation into a M. capricolum recipient cell to create new M. mycoides cells that are controlled only by the synthetic chromosome. The only DNA in the cells is the designed synthetic DNA sequence, including watermark sequences and other designed gene deletions and polymorphisms, and mutations acquired during the building process. The new cells have expected phenotypic properties and are capable of continuous self-replication.. ...
Do Mac viruses exist? In a nutshell, yes. Wondering why? Heres the thing: lots of people refer to all forms of malicious code as viruses. Strictly speaking, this is a misconception because computer viruses are programs that exhibit self-replication capabilities.. However, there is an aspect that blurs the categorization. Present-day malware can be modular, which means it comes with several components under the same hood. Some of these modules are tasked with contaminating a system, while others perform the propagation part of the job. Additionally . . .. ...
Protein-only (prion) epigenetic elements confer unique phenotypes by adopting alternate conformations that specify new traits. Given the conformational flexibility of prion proteins, protein-only inheritance requires efficient self-replication of the underlying conformation. To explore the cellular …
There cannot be any doubt that Americas renowed upward social mobility is a thing of the past. If anything, the U.S. now excels in the self-replication of economic elites - as Europe did in the 19th century.
As we know, Immunotherapy have the proficiency of multiple-differentiation and infinite proliferation, and Immunotherapy have the characteristics of immune regulation and self-replication. Therefore, it can be used as seed cells to repair the impairment or injuries of various tissues and organs. And in recent years, it has been discovered that Immunotherapy can differentiate into renal intrinsic cells and renal essence cells, so Immunotherapy have the function of repair and rebuild for the damaged kidneys. Whats more, Immunotherapy have the same effective mechanism of micro-chinese medicine osmotherapy, so the two therapies have the function of supplement each other ...
This is common behavior in BOINC projects, especially if you have just switched from another project to RNA World or if the work units of a given BOINC project are very heterogenous compared to each other. RNA World work units are de facto extremely heterogenous in their system requirements. For each computation, a series of small mini simulations is run on the server to estimate the time required for completion on the server. Since your machine differs from our server hardware, information based on the benchmarks performed from time to time on your machine are used to scale the duration determined for that work unit on the server to your machine. This scaling process is good but not perfectly accurate. So, the first work units often differ detectably in completion time from what the progress bar indicates. But, with more and more work units of that type pouring in on your system, a BOINC-integrated calculation mechanism corrects for that deviation in a progressive manner. So, with time, this ...
RNA World (beta) is not a project financed by universities or private commercial entities. It runs entirely on donations and money from the members of the e.V. non-profit organisation.. The e.V. yearly budget is only round about 2400,- EUR and RNA World (beta) is only one project of this NPO. Therefore your help is needed to keep the project running: ...
I think the major obstacle to chemical evolution is to explain controlled cell growth. I do not know of a reason why, at the early stages of the Earths history, controlled cell growth should replace uncontrolled cell growth (or dominate before it even uncontrolled cell growth even came to be), because exploding and uncontrolled cell growth of a particular species could result be a Darwinian advantage rather a disadvantage. A controlled cell growth of a multicelluar organism would be disrupted after eating cancer cells for breakfast (unless if it had a cure for cancer built in), thus it is unlikely that a controlled cell growth organism could kill a uncontrolled cell growth organism by eating it, nor would it automatically do so. Cancer requires an energy source like any other life. It acquires growth through sugar and fat. Once you got those and some other essentials such as proteins, you can support the growth of cancer. Cancer is not inhibited by a cell clock, which in itself requires ...
UV-driven photoredox processing of cyanocuprates can generate simple sugars necessary for prebiotic synthesis. We investigate the wavelength dependence of this process from 215 to 295 nm and generally observe faster rates at shorter wavelengths. The most efficient wavelengths are accessible to a range of pot
Understanding the presuppositions and goals of the researchers to properly read the secular literature carefully, especially with chemical evolution (abiogenesis)
Jacob, D., J. Crawford, M. Kleb, V. Conners, R. Bendura, J. Raper, G. Sachse, J. Gille, and L. Emmons, The transport and chemical evolution over the Pacific (TRACE-P) mission: Design, execution, and overview of first results, J. Geophys. Res., 108(D20), 8781, doi:10.1029/2002JD003276, in press, 2003 ...
For the first time, a unified chemical pathway provides all four RNA building blocks needed to kick-start life under plausible prebiotic conditions.
Replicators are fundamental to the origin of life and evolvability. Their survival depends on the accuracy of replication and the efficiency of growth relative to spontaneous decay. Infrabiological systems are built of two coupled autocatalytic systems, in contrast to minimal living systems that must comprise at least a metabolic subsystem, a hereditary subsystem and a boundary, serving respective functions. Some scenarios prefer to unite all these functions into one primordial system, as illustrated in the lipid world scenario, which is considered as a didactic example in detail. Experimentally produced chemical replicators grow parabolically owing to product inhibition. A selection consequence is survival of everybody. The chromatographized replicator model predicts that such replicators spreading on surfaces can be selected for higher replication rate because double strands are washed away slower than single strands from the surface. Analysis of real ribozymes suggests that the error ...
Page contains details about transposase oligomers-encapsulated lipid-based nanoparticle-like protocells . It has composition images, properties, Characterization methods, synthesis, applications and reference articles :
We consider a generic protocell model consisting of any conservative chemical reaction network embedded within a membrane. The membrane results from the self-assembly of a membrane precursor and is se
The problem of the start of biological evolution in the ancient RNA world is considered. It is postulated that the appearance of catalytic RNAs - ribozymes - via spontaneous cis- and trans-rearrangeme
To the Editor The Times Literary Supplement The RNA World Sir: Having with indignation rejected the assumption that the creation of life required an intelligent…
The crux of the argument is the evaluation of P(E,~S). The intuition of many would be to judge this probability large. Matters become stickier when asked to provide a reason for their intuition. The Many Worlds hypothesis is one such response. This is like asking what is the probability of a coin flipped a very large (effectively infinite) number of times landing on its edge? Given a nearly infinite number of tries even an astronomically low probability event will occur. By this means the event E, despite its seeming low probability, will occur. As a consequence, P(E,~S) will be judged large. What is missing in your Bayesian description is the Background or context in which the judgment is made. We might say, e.g., that P(E,~S & ~ManyWorlds) to be very small and the P(E,~S & ManyWorlds) is large. I suppose we could compare the ManyWorlds hypothesis and the hypothesis of the existence of an intelligent designer. There is one possibility favored by many: the Just-Is hypothesis. This ...
Organic Geochemistry serves as the only dedicated medium for the publication of peer-reviewed research on all phases of geochemistry in which organic...
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Less Can Be More: RNA-Adapters May Enhance Coding Capacity of Replicators. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
BCs new Center for Isotope Geochemistry gives the Department of Earth & Environmental Sciences and other researchers the latest technology to study earth materials dating as far back as 4 billion years.
The interpretation of quick tandem repeat (STR) profiles will be difficult when, for instance, alleles are masked due to allele sharing amongst contributors and/or when […]. ...
FindAPhD. Search Funded PhD Research Projects in Geochemistry, self. Search for PhD funding, scholarships & studentships in the UK, Europe and around the world.
a b c Ambrosio, A. L., Boyle, J. A., & Di Pietro, S. M. (2012). Mechanism of platelet dense granule biogenesis: study of cargo ... Biogenesis[edit]. The dense granule is very important in the coagulation cascade because of the bleeding disorders caused by a ...
Biogenesis[edit]. Main article: Ribosome biogenesis. In bacterial cells, ribosomes are synthesized in the cytoplasm through the ...
tRNA biogenesis[edit]. In eukaryotic cells, tRNAs are transcribed by RNA polymerase III as pre-tRNAs in the nucleus.[53] RNA ... "Biogenesis and function of tRNA fragments during sperm maturation and fertilization in mammals". Science. 351 (6271): 391-396 ...
The season finale, "Biogenesis", earned a Nielsen rating of 9.4, with a 14 share, and was viewed by 15.86 viewers, marking a 22 ... "Biogenesis" was viewed by 15.86 whereas "The End" was viewed by 18.76 million viewers. Subtracting the two figures and then ... "Biogenesis" was viewed by 15.86 whereas "The Beginning" was viewed by 20.34 million viewers. Subtracting the two figures and ... Rob Bowman (Director); Chris Carter & Frank Spotnitz (Writers). "Biogenesis". The X-Files. Season 6. Episode 22. Fox. Carter, ...
147-156 Rob Bowman (Director); Chris Carter & Frank Spotnitz (Writers). "Biogenesis". The X-Files. Season 6. Episode 22. Fox. ... "Biogenesis"/"The Sixth Extinction"/"Amor Fati" arc the "best" of the set. Jeffrey Robinson from DVD Talk, was more critical, ... "Biogenesis"/"The Sixth Extinction"/"Amor Fati" trio of episodes started a new mythology for the series, questioning the origin ...
... a project aiming at exploring and understanding mountain biodiversity bioGENESIS - a project aiming at providing an ... ". "bioGENESIS". "bioDISCOVERY". "ecoSERVICES". "bioSUSTAINABILITY". "agroBIODIVERSITY". "ecoHEALTH". "freshwaterBIODIVERSITY ...
Rob Bowman (director); Chris Carter & Frank Spotnitz (writers). "Biogenesis". The X-Files. Season 6. Episode 22. Fox. Tony ...
"Biogenesis". The X-Files. Season 6. Episode 22. Fox. CS1 maint: discouraged parameter (link) Michael W. Watkins (director), ... ", "Biogenesis", "The Sixth Extinction II: Amor Fati") Maggie Wheeler ("Born Again") Dana Wheeler-Nicholson ("Syzygy") Bernard ...
147-156 Rob Bowman (Director); Chris Carter & Frank Spotnitz (Writers). "Biogenesis". The X-Files. Season 6. Episode 22. Fox. ... "Biogenesis"/"The Sixth Extinction"/"Amor Fati" trio of episodes started a new mythology for the series, questioning the origin ... " "Biogenesis" Season 7: "The Sixth Extinction" "The Sixth Extinction II: Amor Fati" "Sein und Zeit" "Closure" "En Ami" " ...
Parker, W.; Roberts, J.S. (1967). "Sesquiterpene Biogenesis". Quart. Rev. 21 (3): 331-363. doi:10.1039/qr9672100331.. ...
"Paul N. Temple". BioGenesis Enterprises. Archived from the original on 2009-06-05. Retrieved 2009-07-03. "Paul N. Temple". ... was the Chairman Emeritus and co-founder of the Institute of Noetic Sciences and the Chairman of the Board of BioGenesis ...
Chloroplast Biogenesis. pp. 155-242. doi:10.1007/978-94-017-0247-8_4. ISBN 978-90-481-6415-8. Biswal, Udaya C.; Biswal, Basanti ... Chloroplast Biogenesis. pp. 155-242. doi:10.1007/978-94-017-0247-8_4. ISBN 978-90-481-6415-8. v t e. ...
The biogenesis of the peroxisomal membrane and the insertion of peroxisomal membrane proteins (PMPs) requires the peroxins ... Lazarow PB, Fujiki Y (1985). "Biogenesis of peroxisomes". Annual Review of Cell Biology. 1: 489-530. doi:10.1146/annurev.cb. ... Lazarow PB, Fujiki Y (Nov 1985). "Biogenesis of peroxisomes". Annual Review of Cell Biology. 1 (1): 489-530. doi:10.1146/ ... There are currently 36 known proteins involved in peroxisome biogenesis and maintenance, called peroxins, which participate in ...
doi:10.1016/0031-9422(88)87026-2. Leete E, Marion L, Spenser ID (October 1954). "Biogenesis of hyoscyamine". Nature. 174 (4431 ...
... proteins encoded by PEX genes that are critical for normal peroxisome assembly and biogenesis. Peroxisome biogenesis disorders ... Weller, S.; Gould, S. J.; Valle, D. (2003). "Peroxisome Biogenesis Disorders". Annual Review of Genomics and Human Genetics. 4 ... Steinberg, S.; Dodt, G.; Raymond, G.; Braverman, N.; Moser, A.; Moser, H. (2006). "Peroxisome biogenesis disorders". Biochimica ... CS1 maint: discouraged parameter (link) GeneReviews/NCBI/NIH/UW entry on Peroxisome Biogenesis Disorders, Zellweger Syndrome ...
Bettencourt-Dias, Mónica; Glover, David M (September 2009). "SnapShot: Centriole Biogenesis". Cell. 136 (1): 188.e1-188.e2. doi ...
Krüger E, Kloetzel PM, Enenkel C (2001). "20S proteasome biogenesis". Biochimie. 83 (3-4): 289-93. doi:10.1016/S0300-9084(01) ...
GeneReviews: Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum Krause, C.; Rosewich, H.; Thanos, M.; Gärtner, J. ( ... Infantile Refsum disease is one of three peroxisome biogenesis disorders which belong to the Zellweger spectrum of peroxisome ... Infantile Refsum disease (IRD), is a rare autosomal recessive congenital peroxisomal biogenesis disorder within the Zellweger ... GeneReviews/NCBI/NIH/UW entry on Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum OMIM entries on Peroxisome ...
Leete E, Marion L, Sspenser ID (October 1954). "Biogenesis of Hyoscyamine". Nature. 174 (4431): 650-1. Bibcode:1954Natur.174.. ...
SI: Chloroplast Biogenesis. 1847 (9): 779-85. doi:10.1016/j.bbabio.2014.12.010. PMID 25585161. Nishikura K (2010). "Functions ... The influence of rRNA modification on eukaryotic ribosome biogenesis and function". RNA Biology. 14 (9): 1138-1152. doi:10.1080 ...
Wilfling, Florian; Haas, J.; Walther, T.; Farese, R. (August 2014). "Lipid droplet biogenesis". Current Opinion in Cell Biology ...
GeneReviews: Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum Krause, C.; Rosewich, H.; Thanos, M.; Gärtner, J. ( ... Zellweger syndrome is one of three peroxisome biogenesis disorders which belong to the Zellweger spectrum of peroxisome ... Steinberg, S.; Dodt, G.; Raymond, G.; Braverman, N.; Moser, A.; Moser, H. (2006). "Peroxisome biogenesis disorders". Biochimica ... "Identification of novel mutations and sequence variation in the Zellweger syndrome spectrum of peroxisome biogenesis disorders ...
Parham R, Rebeiz CA (1992). "Chloroplast biogenesis: [4-vinyl] chlorophyllide a reductase is a divinyl chlorophyllide a- ... Parham R, Rebeiz CA (1995). "Chloroplast biogenesis 72: a [4-vinyl]chlorophyllide a reductase assay using divinyl ... Kolossov VL, Rebeiz CA (2001). "Chloroplast biogenesis 84: solubilization and partial purification of membrane-bound [4-vinyl] ... Biosynthesis of chlorophylls Tripathy BC; Rebeiz CA (1988). "Chloroplast biogenesis 60. Conversion of divinyl ...
BiogenesisEdit. CRISPR-RNA (crRNA), which later guides the Cas nuclease to the target during the interference step, must be ... "Biogenesis pathways of RNA guides in archaeal and bacterial CRISPR-Cas adaptive immunity". FEMS Microbiology Reviews. 39 (3): ...
"Archaeal cell surface biogenesis". FEMS Microbiology Reviews. 42 (5): 694-717. doi:10.1093/femsre/fuy027.. ...
In plants, the miRNA biogenesis pathway is somewhat different; neither Drosha nor DGCR8 has a homolog in plant cells, where the ... Winter J, Jung S, Keller S, Gregory RI, Diederichs S (March 2009). "Many roads to maturity: microRNA biogenesis pathways and ... Microprocessor is also found to be involved in ribosomal biogenesis specifically in the removal of R-loops and activating ... Axtell MJ, Westholm JO, Lai EC (2011). "Vive la différence: biogenesis and evolution of microRNAs in plants and animals". ...
Curran SP, Koehler CM (2004). Mitochondrial Function and Biogenesis. Springer. p. 59. ISBN 9783540214892.. ...
Mitochondrial Function and Biogenesis. Topics in Current Genetics. 8. Berlin, Heidelberg: Springer. pp. 1-35. doi:10.1007/ ...
Jacob M. Schrøder (2011). EB1 and EB3 promote cilia biogenesis by several centrosome-related mechanisms. J Cell Sci 124: 2539- ... Current Opinion in Cell Biology 2013, 25:506-511 Deborah A. Klos Dehring (2013). Deuterosome-Mediated Centriole Biogenesis. ... analyses reveal a novel function of the nucleotide-binding domain of gamma-tubulin in the regulation of basal body biogenesis. ...
"Entrez Gene: TSNAX translin-associated factor X". Ha M, Kim VN (Aug 2014). "Regulation of microRNA biogenesis". Nature Reviews ...
... to establish the principle of biogenesis-namely, that organisms arise only by the reproduction of other organisms. Fundamental ... to establish the principle of biogenesis-namely, that organisms arise only by the reproduction of other organisms. Fundamental ...
Molecular mechanisms governing eukaryotic ribosome biogenesis. *Regulation of ribosome biogenesis by major cell signaling ... Ribosome Biogenesis. Robin E. Stanley, Ph.D. Stadtman Investigator Tel 984-287-3568 [email protected] Curriculum Vitae ... Ribosome biogenesis is one of the most energetically costly endeavors for a cell, at times using up to 80 percent of cellular ... Eukaryotic ribosome biogenesis is a complex process that involves the assembly of 79 ribosomal proteins with 4 ribosomal RNAs ...
Kawaguchi K., Imanaka T. (2019) Peroxisome Biogenesis. In: Imanaka T., Shimozawa N. (eds) Peroxisomes: Biogenesis, Function, ... Joshi AS et al (2018) Lipid droplet and peroxisome biogenesis occur at the same ER subdomains. Nat Commun 9(1):2940PubMed ... Gotte K et al (1998) Pex19p, a farnesylated protein essential for peroxisome biogenesis. Mol Cell Biol 18(1):616-628PubMed ... Lazarow PB, Fujiki Y (1985) Biogenesis of peroxisomes. Annu Rev Cell Biol 1:489-530CrossRefGoogle Scholar ...
Biogenesis is the production of new living organisms. Conceptually, biogenesis sometimes attributed to Louis Pasteur[citation ... The term biogenesis was coined by Henry Charlton Bastian to mean the generation of a life form from nonliving materials; ... Biogenesis and Abiogenesis: Critiques and Addresses Evolutionary biology portal. ... however, Thomas Henry Huxley chose the term abiogenesis and redefined biogenesis for life arising from preexisting life. The ...
Use features like bookmarks, note taking and highlighting while reading Biogenesis. ... Biogenesis - Kindle edition by Tatsuaki Ishiguro. Download it once and read it on your Kindle device, PC, phones or tablets. ... Biogenesis and Other Stories collects five stories by Tatsuaki Ishiguro.. In Biogenesis, two professors research the rare ... Biogenesis by Tatsuaki Ishiguro is difficult to discuss. I thoroughly enjoyed the books four stories and am writing this to ...
The yeast, S. cerevisiae is the eukaryotic model organism for the study of ribosome biogenesis. Ribosome biogenesis starts in ... Ribosome biogenesis is a very tightly regulated process, and it is closely linked to other cellular activities like growth and ... Ribosome biogenesis is the process of making ribosomes. In prokaryotes, this process takes place in the cytoplasm with the ... The release of the biogenesis factors is mediated mostly by GTPases such as Lsg1 and ATPases such as Drg1. The precise sequence ...
Evidence for the biogenesis of trans-(1β-H; 5a-H)-guaianolides. Tetrahedron Letters 24: 969-972.CrossRefGoogle Scholar ... Evidence for the biogenesis of 1a-hydroxy-trans-eudesmanolides. J. Chem. Soc. Perkin 1, 1982: 881-884.CrossRefGoogle Scholar ... The biogenesis and chemistry of sesquiterpene lactones. In: Prog. Chem. Org. Nat. Prod. (W. Herz, H. Grisebach, G.W. Kirby, eds ... The biogenesis of sesquiterpene lactones of the Compositae. In: Recent Advances in Phytochemistry (V. C. Runeckles, T. J. Mabry ...
Biogenesis and Abiogenesis.-According to their Greek derivation these two terms refer to the origin of life. Biogenesis is the ... Hence the distinction between abiogenesis and biogenesis. Let us examine which view harmonizes best with the facts actually ...
Protein which is involved in the formation, organization, maintenance and degradation of the cilium, a cell surface projection found at the surface of a large proportion of eukaryotic. Their most prominent structural component is the axoneme which consists of nine doublet microtubules, with all motile cilia - except those at the embryonic node - containing an additional central pair of microtubules ...
Brix from xenopus laevis and brx1p from yeast define a new family of proteins involved in the biogenesis of large ribosomal ... It is required for biogenesis of the 60S ribosomal subunit [PMID: 11843177]. ...
Listen to Biogenesis Radio free online. Listen to free internet radio, sports, music, news, talk and podcasts. Stream live ...
We propose a model for piRNA biogenesis in animal germ lines, in which the Zuc endoribonuclease has a key role in primary piRNA ... Primary piRNAs are made by cleavage of longer piRNA cluster transcripts, but the nuclease responsible for their biogenesis was ... depending on their biogenesis machinery5,6,7,8,9,10. Primary piRNAs are processed from long non-coding RNA precursors ... is an endoribonuclease essential for primary piRNA biogenesis. We solved the crystal structure of Drosophila melanogaster Zuc ( ...
Biogenesis Laboratories is the name of an anti-aging clinic in the Miami, FL suburb of Coral Gables, FL at the center of Major ... Tim Elfrink and Gus Garcia-Roberts: Blood Sport: Alex Rodriguez, Biogenesis and the Quest to End Baseballs Steroid Era, Dutton ... Bob Nightengale: "Biogenesis, a year later: MLBs joyless probe endures", USA Today, August 5, 2014. [2] ... Biogenesis had closed abruptly in December of 2012, and Bosch seemingly disappeared shortly after a clinic employee provided ...
... we had a model of peroxisome biogenesis that involved growth and division of preexisting peroxisomes. Today, thanks to ... Peroxisome biogenesis Annu Rev Cell Dev Biol. 2001;17:701-52. doi: 10.1146/annurev.cellbio.17.1.701. ... Peroxisome biogenesis is remarkably conserved among eukaryotes. A group of fatal, inherited neuropathologies are recognized as ... Fifteen years ago, we had a model of peroxisome biogenesis that involved growth and division of preexisting peroxisomes. Today ...
... biogenesis, tRNA molecules undergo extensive processing before they can fulfill their essential role as the adapter molecule in ... tRNA biogenesis requires multiple processing events. Precursor tRNA. transcripts (top) contain 5′‐leader and 3′‐trailer ... tRNA Biogenesis. Jane E Jackman, The Ohio State University, Columbus, Ohio, USA ... During transfer ribonucleic acid (tRNA) biogenesis, tRNA molecules undergo extensive processing before they can fulfill their ...
Related "Biogenesis of America" Articles. Miami-Dade News Cooperation leads to shorter sentence for baseball drug clinic owner ... Biogenesis of America. Cooperation leads to shorter sentence for baseball drug clinic owner in South Florida. The former owner ... Assistant U.S. Attorney Sharad Motiani said Bosch, who ran the now-closed Biogenesis of America clinic in Coral Gables, ... Influential agent Scott Boras issued a statement Friday in response to Newsday reporting that Biogenesis founder Anthony Bosch ...
Given his connection to the under-investigation Biogenesis Clinic, Alex Rodriguez is probably the last player Major League ... Given his connection to the under-investigation Biogenesis Clinic, Alex Rodriguez is probably the last player Major League ...
The Nucleolus and Ribosome Biogenesis. Authors. * A.A. Hadjiolov Series Title. Cell Biology Monographs. Series Volume. 12. ... studies on the biogenesis of ribosomes expanded rapidly to become a core topic in molecular genetics. ...
Related "Biogenesis of America" Articles. Breaking Sports Criminal charges filed in Biogenesis doping scandal. The U.S. ... Biogenesis of America. Criminal charges filed in Biogenesis doping scandal. The U.S. government on Tuesday filed criminal ... What spurred MLB investigation? Disgruntled Biogenesis employee Lance Pugmire. An employee deprived of a $4,000 investment - ... Pitcher C.J. Wilson had harsh words for the 13 players suspended in the wake of the Biogenesis investigation on Monday, ...
... Noam Shomron. 1 and Carmit Levy2. 1Department of Cell and Developmental ... 2. Intronic miRNA Biogenesis in Light of Pre-mRNA Splicing. Relationships between intronic miRNAs and the processing events of ... The canonical miRNA biogenesis pathway and its affect on gene expression. Elaborated mechanisms and exceptions to this pathway ... W. Filipowicz and V. Pogacic, "Biogenesis of small nucleolar ribonucleoproteins," Current Opinion in Cell Biology, vol. 14, no ...
Biogenesis of bacterial membrane vesicles.. Deatherage BL1, Lara JC, Bergsbaken T, Rassoulian Barrett SL, Lara S, Cookson BT. ... These data support a model of MV biogenesis, wherein bacterial growth and division invoke temporary, localized reductions in ...
Ribosomal protein L1/ribosomal biogenesis protein (IPR028364). Short name: Ribosomal_L1/biogenesis ... This entry also matches ribosome biogenesis proteins, such as Cic1, which associates with the proteasome and is required for ...
A conserved phosphatase cascade that regulates nuclear membrane biogenesis. Youngjun Kim, Matthew S. Gentry, Thurl E. Harris, ... A conserved phosphatase cascade that regulates nuclear membrane biogenesis. Youngjun Kim, Matthew S. Gentry, Thurl E. Harris, ... A conserved phosphatase cascade that regulates nuclear membrane biogenesis. Youngjun Kim, Matthew S. Gentry, Thurl E. Harris, ... A conserved phosphatase cascade that regulates nuclear membrane biogenesis Message Subject (Your Name) has sent you a message ...
Multivesicular endosome biogenesis in the absence of ESCRTs.. Stuffers S1, Sem Wegner C, Stenmark H, Brech A. ... Even though ESCRT proteins appear to be essential for the biogenesis of MVEs in Saccharomyces cerevisae, it is not clear ... Our observations suggest that both ESCRT-dependent and ESCRT-independent mechanisms of MVE biogenesis exist in mammalian cells. ... whether ESCRT-independent pathways for MVE biogenesis exist in higher organisms. In this study we maximized inhibition of ESCRT ...
Extracellular signaling proteins encoded by the hedgehog (hh) multigene family are responsible for the patterning of a variety of embryonic structures in vertebrates and invertebrates. The Drosophila hh gene has now been shown to generate two predominant protein species that are derived by an internal autoproteolytic cleavage of a larger precursor. Mutations that reduced the efficiency of autoproteolysis in vitro diminished precursor cleavage in vivo and also impaired the signaling and patterning activities of the HH protein. The two HH protein species exhibited distinctive biochemical properties and tissue distribution, and these differences suggest a mechanism that could account for the long- and short-range signaling activities of HH in vivo. ...
Significant advances have been made in elucidating the biogenesis pathway and three-dimensional structure of the UsnRNPs, the ... Spliceosomal UsnRNP biogenesis, structure and function Curr Opin Cell Biol. 2001 Jun;13(3):290-301. doi: 10.1016/s0955-0674(00) ... Significant advances have been made in elucidating the biogenesis pathway and three-dimensional structure of the UsnRNPs, the ...
Biogenesis is a recognized leader in the supply of monoclonal and polyclonal antibodies and custom manufacturing services to ... Biogenesis Ltd company data, news, contact details and stock information. ... More Information about "Biogenesis Ltd" on BioPortfolio. We have published hundreds of Biogenesis Ltd news stories on ... Biogenesis Ltd. Biogenesis is a recognized leader in the supply of monoclonal and polyclonal antibodies and custom ...
Nicotinamide Riboside and Mitochondrial Biogenesis. The safety and scientific validity of this study is the responsibility of ... The Role of Nicotinamide Riboside in Mitochondrial Biogenesis. Brief Summary Mitochondria are important parts of the cell that ... Mitochondrial biogenesis - Magnetic Resonance Imaging [ Time Frame: 4 weeks ]. Change in in vivo measurement of mitochondrial ... Mitochondrial biogenesis - mitochondrial DNA quantification [ Time Frame: 4 weeks ]. Change from baseline in the amount of ...
... Kleylein-Sohn J., Westendorf J., Le Clech M., Habedanck R., Stierhof Y.-D., ... Collectively, these data afford a comprehensive view of the assembly pathway underlying centriole biogenesis in human cells. ...
Find the most comprehensive real-world treatment information on Biogenesis Muscle Aid at PatientsLikeMe. 0 patients with ... bipolar I disorder or psoriasis currently take Biogenesis Muscle Aid. ... Stopped taking Biogenesis Muscle Aid Duration. Patients. This item is relevant to you: 2 - 5 years 1 * 1 ... What is Biogenesis Muscle Aid?. Category: Supplements false Muscle-Aid is a dietary supplement that includes malic acid, L- ...
  • The Nucleolar Integrity Group investigates the regulation and molecular mechanisms of ribosome biogenesis through a multidisciplinary combination of structural, molecular, and cellular biology. (
  • Eukaryotic ribosome biogenesis is a complex process that involves the assembly of 79 ribosomal proteins with 4 ribosomal RNAs through the concerted effort of more than 200 non-ribosomal biogenesis factors within the nucleolus of the cell. (
  • Ribosome biogenesis is one of the most energetically costly endeavors for a cell, at times using up to 80 percent of cellular energy resources. (
  • Ribosome biogenesis is the process of making ribosomes. (
  • Ribosome biogenesis is a very tightly regulated process, and it is closely linked to other cellular activities like growth and division. (
  • Some have speculated that in the origin of life, ribosome biogenesis predates cells, and that genes and cells evolved to enhance the reproductive capacity of ribosomes. (
  • The yeast, S. cerevisiae is the eukaryotic model organism for the study of ribosome biogenesis. (
  • Ribosome biogenesis starts in the nucleolus. (
  • During transfer ribonucleic acid (tRNA) biogenesis, tRNA molecules undergo extensive processing before they can fulfill their essential role as the adapter molecule in translation, bringing amino acids into the ribosome for protein synthesis. (
  • The relatively simple structure of the ribosome strengthens the hope that a full understanding of the structure and function of this organelle in molecular terms is within the reach of contemporary research~ Since each of the rRNA and protein molecules embodied in the ribosome is the product of a distinct gene, studies on the biogenesis of ribosomes expanded rapidly to become a core topic in molecular genetics. (
  • This entry also matches ribosome biogenesis proteins, such as Cic1, which associates with the proteasome and is required for the degradation of specific substrates [ PMID: 11500370 ], and for the synthesis of 60S ribosome subunits [ PMID: 14623999 ]. (
  • Diverse Regulators of Human Ribosome Biogenesis Discovered by Changes in Nucleolar Number. (
  • Ribosome biogenesis is a highly regulated, essential cellular process. (
  • Although studies in yeast have established some of the biological principles of ribosome biogenesis, many of the intricacies of i. (
  • Granneman S and Baserga SJ (2004) Ribosome biogenesis: of knobs and RNA processing. (
  • Discovery of a small molecule that inhibits bacterial ribosome biogenesis. (
  • While small molecule inhibitors of the bacterial ribosome have been instrumental in understanding protein translation, no such probes exist to study ribosome biogenesis. (
  • This work establishes lamotrigine as a widely available chemical probe of bacterial ribosome biogenesis and suggests a role for E. coli IF2 in ribosome assembly. (
  • Furthermore, recent studies have demonstrated that defects in ribosome biogenesis are associated with several hereditary diseases. (
  • In this Cell Science at a Glance article and the accompanying poster, we summarise the current knowledge on eukaryotic ribosome biogenesis, with an emphasis on the yeast model system. (
  • With the help of selected examples, in this Cell Science at a Glance article and the accompanying poster, we highlight emerging concepts in the ribosome biogenesis field in yeast and higher eukaryotes, as well as diseases that are caused by mutations in associated factors (see Box 1 ). (
  • Ribosome biogenesis begins in the nucleolus, where three of the rRNA species, the 18S, 5.8S and 25S, are co-transcribed by RNA polymerase I (Pol I) as a single polycistronic transcript (see poster). (
  • It is known that many proteins, called "peroxins", are encoded by PEX genes and involved in peroxisome biogenesis, including the targeting of peroxisomal matrix and membrane proteins. (
  • Brix from xenopus laevis and brx1p from yeast define a new family of proteins involved in the biogenesis of large ribosomal subunits. (
  • Even though ESCRT proteins appear to be essential for the biogenesis of MVEs in Saccharomyces cerevisae, it is not clear whether ESCRT-independent pathways for MVE biogenesis exist in higher organisms. (
  • The paralogous Brr6 and Brl1 are conserved integral membrane proteins of the nuclear envelope (NE) with an unclear role in nuclear pore complex (NPC) biogenesis. (
  • Our results suggest that mitochondrial biogenesis, oxidative metabolic pathways, and OXPHOS proteins in SAT are downregulated in acquired obesity, and are associated with metabolic disturbances already at the preclinical stage. (
  • This review will summarize the current knowledge on the biogenesis of the replicative structures, the membrane anchoring of the replication-transcription complexes, and the location of viral RNA synthesis, with particular focus on the dynamics of the coronavirus replicative structures and individual replication-associated proteins. (
  • The BfpE protein of enteropathogenic E. coli (EPEC) is a representative of a family of cytoplasmic membrane proteins that participate in the biogenesis of type IV pili. (
  • One of the obstacles that has limited progress has been the absence of an experimental setup visualizing membranes, which would allow to directly assess the function of the Atg proteins during autophagosome biogenesis. (
  • Regulatory proteins and signaling pathways associated with induced biogenesis and trafficking of MVBs during plant immune responses have also been identified and characterized. (
  • The topics include mitochondial DNA genetics and the heteroplasmy conundrum in evolution and disease, mitochondrial biogenesis through the activation of nuclear signaling proteins, mechanism of mitochondrial fission and fusion, altered sulfide metabolism in ethylmalonic encephalopathy, and the relevance of mitochondial genetics and metabolism in cancer development. (
  • Some scientists think that increasing the number of mitochondria in the body (mitochondrial biogenesis) might be an effective treatment for the symptoms of mitochondrial disease. (
  • Bandlow, W. is the author of 'Mitochondria 1977 : Genetics and Biogenesis of Mitochondria', published 1977 under ISBN 9783110073218 and ISBN 3110073218. (
  • Earlier activation of mitochondrial biogenesis through these pathways will accelerate the generation of new mitochondria, thereby ensuring energy-producing capability for when other factors for axonal growth are synthesized. (
  • Each cell has a herd of mitochondria, dividing like bacteria ( mitochondrial biogenesis ) and removed by quality control mechanisms when damaged ( mitophagy ). (
  • Accumulation of damaged mitochondria triggers SKN-1 activation, which initiates a bipartite retrograde signaling pathway stimulating the coordinated induction of both mitochondrial biogenesis and mitophagy genes. (
  • Age-dependent decline of mitophagy both inhibits removal of dysfunctional or superfluous mitochondria and impairs mitochondrial biogenesis resulting in progressive mitochondrial accretion and consequently, deterioration of cell function. (
  • Cell-Fuel helps to support optimal mitochondrial function and mitochondrial biogenesis or the formation of new mitochondria. (
  • We know how Hyperbaric therapy works--it works by reviving the little mitochondria and actually causes mitochondrial biogenesis , so that if you need more mitochondria in your neurons more of them will form. (
  • Hyperbaric therapy what you need to know: "we know how hyperbaric therapy works--it works by reviving the little mitochondria & actually causes mitochondrial biogenesis, so that if you need more mitochondriain your neurons more of them will form. (
  • Biogenesis Laboratories is the name of an anti-aging clinic in the Miami, FL suburb of Coral Gables, FL at the center of Major League Baseball 's biggest PED scandal since the BALCO affair. (
  • Alex Rodriguez's cousin Yuri Sucart, who supplied the New York Yankees star with steroids, has been sentenced to seven months in prison for his role in Major League Baseball's Biogenesis scandal. (
  • Miguel Tejada will not be disciplined in the Biogenesis scandal. (
  • Major League Baseball released a statement Wednesday clearing Miguel Tejada of any discipline involving the Biogenesis scandal. (
  • And so I think have been falsely accused throughout the media," he told ESPN's Pedro Gomez on Monday in his first comments since the Biogenesis clinic scandal broke in January. (
  • GREENE: So Biogenesis, this clinic that's been implicated in the current Major League baseball doping scandal, remind us exactly who they are. (
  • MITOPLD is a mitochondrial protein essential for nuage formation and piRNA biogenesis in the mouse germline. (
  • The yeast data suggest there is a critical signaling cascade involving the Nem1p/Spo7p protein complex and Smp2p, and that this pathway plays a critical role in nuclear membrane biogenesis ( 24 - 26 ). (
  • Thus, a mitogen-activated protein kinase-dependent mechanism regulates autophagy by controlling the biogenesis and partnership of two distinct cellular organelles. (
  • We subjected adult male rats to ischemia, followed by either treadmill exercise or non-exercise and analyzed the effect of exercise on the amount of mitochondrial DNA (mtDNA), expression of mitochondrial biogenesis factors, and mitochondrial protein. (
  • Two independently isolated, temperature-sensitive strains that were also defective for karmellae biogenesis carried mutations in VPS16 , a gene involved in vacuolar protein sorting. (
  • During β-carboxysome biogenesis, Rubisco first aggregates, mediated by the protein CcmM, followed by shell formation. (
  • this protein is known to play an important role in activating mitochondrial biogenesis and oxidative metabolism (Wu et al. (
  • The canonical miRNA biogenesis pathway and its affect on gene expression. (
  • Significant advances have been made in elucidating the biogenesis pathway and three-dimensional structure of the UsnRNPs, the building blocks of the spliceosome. (
  • 2-Methoxyestradiol Affects Mitochondrial Biogenesis Pathway and Succinate Dehydrogenase Complex Flavoprotein Subunit A in Osteosarcoma Cancer Cells. (
  • Collectively, these data afford a comprehensive view of the assembly pathway underlying centriole biogenesis in human cells. (
  • Nicotinamide riboside (NR), a NAD+ natural precursor, boosts the PGC1α-dependent mitochondrial biogenesis pathway, leading to increased transcription of genes of the oxidative phosphorylation and improved motor performance of myopathic mice. (
  • For simplicity, the widely used term "miRNA biogenesis" hereafter refers to the initial step of miRNA excision from its RNA transcript. (
  • Dysregulation of miRNA biogenesis machinery and miRNA/RNA ratio in skeletal muscle of ALS mice. (
  • Here we investigate the regulation of the members of the miRNA biogenesis pathw. (
  • Our study reveals a chloroplast-to-nucleus signaling mechanism that favors miRNA biogenesis under heat and possibly other environmental perturbations. (
  • NEW YORK (GenomeWeb) - A team led by MD Anderson Cancer Center researchers this month published new data demonstrating that breast cancer-derived exosomes are capable of cell-independent microRNA biogenesis and are able to promote tumorigenesis in a Dicer-dependent manner. (
  • Chloroplast-to-Nucleus Signaling Regulates MicroRNA Biogenesis in Arabidopsis. (
  • Biogenesis of bacterial membrane vesicles. (
  • Therefore, we propose that Dullard participates in a unique phosphatase cascade regulating nuclear membrane biogenesis, and that this cascade is conserved from yeast to mammals. (
  • Successful replication of Toxoplasma requires substantial membrane biogenesis, which must be satisfied irrespective of the host-cell milieu. (
  • Assistant U.S. Attorney Sharad Motiani said Bosch, who ran the now-closed Biogenesis of America clinic in Coral Gables, revealed key evidence against at least four other people including a self-style chemist who supplied drugs made in his suburban garage and a. (
  • Tim Elfrink of the Miami New Times originally listed Cruz in his jaw-dropping January report that connected some of baseball's biggest stars to Tony Bosch's Biogenesis of America clinic. (
  • Biogenesis of America is now defunct, but was a rejuvenation clinic based in Florida who provided a number of MLB players with performance-enhancing drugs, specifically HGH. (
  • A Miami New Times report from January 2013, which sparked MLB's investigation, said Rodriguez had bought human growth hormone and other substances from 2009 to 2012 from Bosch's clinic, Biogenesis of America. (
  • Filipowicz W and Pogacic V (2002) Biogenesis of small nucleolar ribonucleoproteins. (
  • Major League Baseball had the choice of going after the 2002 American League MVP for the Biogenesis case, as the league did 13 other players earlier this month, or for the amphetamine case. (
  • Peroxisome biogenesis disorders (PBD) are a group of inherited conditions caused by faulty assembly of peroxisomes, structures located inside cells that regulate levels of important fats and lipids in the body. (
  • The Peroxisome Biogenesis Disorders (PBD) are a group of inherited disorders due to defects in peroxisome assembly causing complex developmental and metabolic sequelae. (
  • Novel retinal findings in peroxisomal biogenesis disorders. (
  • Peroxisomal biogenesis disorders are caused by disruption of long chain fatty acid metabolism due to mutations in PEX genes. (
  • We are continuing our investigations and hope they will lead us to better understand how sugar metabolism is linked to peroxisomal biogenesis disorders. (
  • This research will not only address the fundamental questions concerning organelle biogenesis and functions in important biological processes, such as cell wall formation and stress signaling pathways in plants, but will also have potential applications for the biotechnology industry in Hong Kong and China, including improving the value of plants as biofuel feedstocks and enhancing crop productivity in high-stress environments. (
  • There are also alternative pathways of centrosome biogenesis. (
  • However, despite the apparent similarities, the various classes of snRNP follow different biosynthetic pathways and most steps of snRNP biogenesis can be linked to distinct subcellular compartments. (
  • Biogenesis had closed abruptly in December of 2012, and Bosch seemingly disappeared shortly after a clinic employee provided the newspaper with incriminating evidence about its activities. (
  • The Angels will face old nemesis Alex Rodriguez on Friday night for the first time since the New York Yankees slugger served a one-year suspension for obtaining illegal performance-enhancing substances from the now-closed Biogenesis anti-aging clinic in. (
  • Given his connection to the under-investigation Biogenesis Clinic, Alex Rodriguez is probably the last player Major League Baseball would want to be ahead of schedule in his recovery from injury. (
  • Pedro Gomez of ESPN reported Tuesday that Biogenesis evidence also implicated Tejada's purchase of performance-enhancing drugs through the Miami clinic that has since closed. (
  • Twelve players accepted 50-game suspensions for their involvement with the Biogenesis clinic, and Alex Rodriguez is looking at a longer suspension pending appeal. (
  • If Biogenesis is the only such clinic, then… well you don't really have to finish that thought, because of course it isn't. (
  • And right now, MLB and the Players Association are no better prepared for the next Biogenesis type of clinic than they were for this one. (
  • Tony Bosch, right, flat-out denied any knowledge of suspected PED distribution at Biogenesis, his closed South Florida clinic, in an interview with ESPN's Pedro Gomez in April. (
  • They're accused of receiving performance enhancing drugs from a Miami clinic called Biogenesis. (
  • FISH: Biogenesis is a anti-aging, wellness clinic that is now shuttered. (
  • After Miami New Times revealed that a local clinic called Biogenesis was selling performance-enhancing drugs to a host of baseball stars, the investigators were tasked with collecting the evidence to suspend them. (
  • Fifteen years ago, we had a model of peroxisome biogenesis that involved growth and division of preexisting peroxisomes. (
  • Peroxisomal biogenesis disorder results from defects in the genes that form the peroxisomes, essential micro-machines inside the cell that are involved in breaking down and producing certain lipids. (
  • Since overexpression of Pex11p in Chinese hamster ovary wild-type cells causes proliferation of peroxisomes, these data suggest that Pex11p plays an important role in peroxisome biogenesis by supporting ARF- and coatomer-dependent vesiculation of the organelles. (
  • R egarding the biogenesis of peroxisomes various concepts have been postulated. (
  • These observations again may ascribe a distinct role to the ER in the biogenesis of peroxisomes. (
  • The transcription factor EB (TFEB), a master gene for lysosomal biogenesis, coordinated this program by driving expression of autophagy and lysosomal genes. (
  • Plk4-induced centriole biogenesis in human cells. (
  • Highlighting the importance of these interactions, mutational disruption of either one of these interactions was sufficient to cripple Plk4-dependent centriole biogenesis. (
  • Brr6 and Brl1 locate to nuclear pore complex assembly sites to promote their biogenesis. (
  • Kiss T (2004) Biogenesis of small nuclear RNPs. (
  • Here we globally monitored mitochondrial and nuclear gene expression processes in Saccharomyces cerevisiae during mitochondrial biogenesis, when OXPHOS complexes are synthesized. (
  • Those claims of misconduct would later be echoed by several other former Biogenesis employees in Alex Rodriguez's lawsuit against MLB. (
  • The biogenesis of ribosomes is a tightly regulated activity and it is inextricably linked to other fundamental cellular processes, including growth and cell division. (
  • Hence the distinction between abiogenesis and biogenesis. (
  • however, Thomas Henry Huxley chose the term abiogenesis and redefined biogenesis for life arising from preexisting life. (
  • this is called theory of biogenesis proved by Louis Pasteur, who has disproved abiogenesis. (
  • In this study, we attempted to determine whether treadmill exercise induces functional improvement through regulation of mitochondrial biogenesis after brain ischemia. (
  • Prevention of disulphide-bond formation in vivo resulted in abnormal carboxysomes, a ~20-fold increase in CO 2 requirement and a ~4-fold slower growth rate of mutant cyanobacteria, supporting the view that redox-regulation in the SSUL module is critical for carboxysome biogenesis and function. (
  • Conceptually, biogenesis sometimes attributed to Louis Pasteur[citation needed] and encompasses the belief that complex living things come only from other living things, by means of reproduction. (
  • Our observations suggest that both ESCRT-dependent and ESCRT-independent mechanisms of MVE biogenesis exist in mammalian cells. (
  • ArthroGenx Cream 2oz by Biogenesis combines botanicals, natural oils, and connective tissue repair compounds for healthy joint support. (
  • The hypersensitivity of 14 vacuole biogenesis mutants to tunicamycin was well correlated with pronounced defects in karmellae assembly, suggesting that the karmellae assembly defect reflected alteration of ER structure or function. (
  • to establish the principle of biogenesis -namely, that organisms arise only by the reproduction of other organisms. (
  • Biogenesis is the production of new living organisms. (
  • Highly evolved organisms like mammals cannot have biogenesis of their lost parts except liver which can be regenerated. (
  • Tony Bosch, el bribonzuelo que las Grandes Ligas han utilizado como su principal testigo en el oscuro caso de la clínica Biogenesis, es un sinvergüenza de oficio. (
  • Anthony Bosch, right, former owner of the Biogenesis of. (
  • Influential agent Scott Boras issued a statement Friday in response to Newsday reporting that Biogenesis founder Anthony Bosch told federal investigators Boras was involved in efforts to cover up Manny Ramirez's use of performance-enhancing drugs in 2009. (
  • The Office of the Commissioner investigated all allegations regarding players associated with Anthony Bosch and Biogenesis. (
  • Bosch supplied evidence that Tejada had been a Biogenesis customer. (
  • Outside The Lines catches up with Biogenesis founder Tony Bosch, who discusses the PED allegations against him. (
  • What Biogenesis revealed is that there were a collection of major-league players who had found a way to violate the terms of the Joint Drug Agreement without being detected during the ordinary enforcement mechanisms of that agreement. (
  • The results of the proposed research should advance our knowledge about the mechanisms involved in the biogenesis of EPEC pili. (
  • The results indicate that exercise can promote mitochondrial biogenesis after ischemic injury, which may serve as a novel component of exercise-induced repair mechanisms of the brain. (
  • However, despite these numerous examples of naturally occurring and experimentally induced ER proliferation, the cellular mechanisms that control regulated ER biogenesis are as yet unclear. (
  • Evidence from various study systems suggests that mitochondrial function and biogenesis are compromised in subcutaneous adipose tissue (SAT) in type 2 diabetes ( 5 ), morbid obesity ( 6 ), and insulin resistance ( 7 ). (
  • Impaired mitochondrial function and excessive mitochondrial content are major characteristics of ageing and several human pathophysiological conditions, highlighting the pivotal role of the coordination between mitochondrial biogenesis and mitophagy. (
  • Mitochondrial function in adipocytes is crucial for adiponectin synthesis with impaired mitochondrial function reducing adiponectin synthesis and raised mitochondrial biogenesis increasing adiponectin synthesis [23]. (
  • miRNAs are processed through a series of post-transcriptional biogenesis steps. (
  • MiRNAs in the biogenesis of trans-acting siRNAs in higher plants. (
  • Here, we show that tocopherols (vitamin E), lipid-soluble antioxidants synthesized from tyrosine in chloroplasts, positively regulate the biogenesis of miRNAs. (
  • PPAR's expression in skeletal muscle is related to the late induction of exercise-induced responses during endurance training, such as increased oxidative capacity of type I muscle fibers and mitochondrial biogenesis (Wang et al. (
  • This study is an open-label experimental medicine study using NR with the primary aim of determining whether there is mechanistic link between mitochondrial biogenesis and physiological function in humans with a similar mitochondrial disease. (
  • Previous studies have suggested both exercise and mitochondrial biogenesis contribute to improved post-ischemic recovery of brain function. (
  • Here, we discuss the biogenesis of SPATEs and their function as toxins. (
  • However, to realize the potential that exRNAs may have as health/disease indicators and/or as therapeutic molecules, fundamental principles of their biogenesis, distribution, uptake, and function need to be defined. (
  • p115 is required for biogenesis of the Golgi apparatus, but it is unclear whether its mechanism of action requires its golgin and/or SNARE interactions. (
  • Surprisingly, however, in vivo tests of the p115/tether interaction have generated controversy concerning its role in Golgi biogenesis and mitotic Golgi disassembly, and in vivo tests of the role of p115/SNARE interactions have not been reported. (
  • Because Golgi biogenesis depends on interactions of p115 in vivo , this raises two critical questions. (
  • It may be p115 binding to SNAREs that is required, but given that general models of SNARE-mediated fusion do not include an activity similar to that proposed for p115, it remains critical to test whether p115/SNARE interactions are required in vivo for ER-to-Golgi transport and Golgi biogenesis. (
  • Karmellae biogenesis was defective in all 13 other vacuole biogenesis mutants tested, although the severity of the karmellae assembly defect varied depending on the particular mutation. (
  • This is important for the understanding of the biology of cell energetics and also relevant for patients with rare mitochondrial diseases where it has been proposed that inducing mitochondrial proliferation (biogenesis) might be an effective treatment. (
  • However, the vacuole biogenesis mutants were able to proliferate their ER in response to Hmg2p, indicating that the mutants did not have a global defect in the process of ER biogenesis. (
  • Antioxidant supplementation reduces skeletal muscle mitochondrial biogenesis. (
  • However, exercise-induced ROS may regulate beneficial skeletal muscle adaptations, such as increased mitochondrial biogenesis. (
  • We therefore investigated the effects of long-term antioxidant supplementation with vitamin E and α-lipoic acid on changes in markers of mitochondrial biogenesis in the skeletal muscle of exercise-trained and sedentary rats. (
  • CONCLUSIONS: : Vitamin E and α-lipoic acid supplementation suppresses skeletal muscle mitochondrial biogenesis, regardless of training status. (
  • The piece revealed former Biogenesis employee Porter Fischer as the whistleblower who'd leaked the clinic's records and included his allegations that Mullin's team had alternately threatened him with legal action and offered thousands of dollars to cooperate. (
  • Biogenesis Dim Pro Plus 60 vcaps nutritionally supports the activity of enzymes that metabolize estrogen and aspirin. (
  • It is required for biogenesis of the 60S ribosomal subunit [ PMID: 11843177 ]. (
  • We propose a model for piRNA biogenesis in animal germ lines, in which the Zuc endoribonuclease has a key role in primary piRNA maturation. (
  • In contrast, the p115 SNARE-interacting domain was required for Golgi biogenesis. (
  • p115 is essential for biogenesis of the Golgi apparatus ( 2 - 4 ). (
  • Thus, p115 may mediate vesicle fusion during Golgi biogenesis in two sequential reactions, initially forming a mitotically regulated giantin-p115-GM130 tether, and later mediating pairing of SNAREs ( 11 ). (
  • The centre focuses on understanding the biogenesis and functions of three organelles, namely, Golgi, TGN and EXPO. (
  • And if you don't find the antibody you are looking for at Biogenesis, you can now order custom monoclonal antibodies from the HuCAL® Gold library in via the Antibodies by Design division of MorphoSys. (
  • Whatever your antibody needs, Biogenesis is ready to provide the quality products and services that you can rely on. (