Biogenesis: 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.Mitochondrial Turnover: The cellular processes involved in adjustments to the MITOCHONDRIAL VOLUME, content, and activity, that depend on the energy demands of the cell.Mitochondria: 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)Ribonuclease III: 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.Mitochondrial Proteins: Proteins encoded by the mitochondrial genome or proteins encoded by the nuclear genome that are imported to and resident in the MITOCHONDRIA.Peroxisomes: 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)Nuclear Respiratory Factor 1: 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.Saccharomyces cerevisiae Proteins: 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.Molecular Sequence Data: 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.Mutation: 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.Saccharomyces cerevisiae: 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.Membrane Proteins: 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.Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Cell Nucleolus: 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)Protein Transport: 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.RNA Processing, Post-Transcriptional: 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.Peroxisomal Disorders: 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.Ribosome Subunits, Large, Eukaryotic: 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.Amino Acid Sequence: 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.MicroRNAs: 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.RNA, Ribosomal: 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)NF-E2-Related Factor 1: A basic-leucine zipper transcription factor that is involved in regulating inflammatory responses, MORPHOGENESIS, and HEME biosynthesis.Organelles: 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, Muscle: Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.RNA Precursors: 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.Hermanski-Pudlak Syndrome: Syndrome characterized by the triad of oculocutaneous albinism (ALBINISM, OCULOCUTANEOUS); PLATELET STORAGE POOL DEFICIENCY; and lysosomal accumulation of ceroid lipofuscin.RNA-Binding Proteins: Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.DNA, Mitochondrial: Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.Melanosomes: Melanin-containing organelles found in melanocytes and melanophores.Ribosomal Proteins: Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.Argonaute Proteins: 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.Fimbriae, Bacterial: 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).Zellweger Syndrome: 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.Nuclear Respiratory Factors: 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.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Protein Binding: 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.RNA Interference: 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.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Iron-Sulfur Proteins: 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.Molecular Chaperones: 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.RNA, Small Interfering: 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.Models, Biological: 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.Endoplasmic Reticulum: 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)Fimbriae Proteins: Proteins that are structural components of bacterial fimbriae (FIMBRIAE, BACTERIAL) or sex pili (PILI, SEX).DEAD-box RNA Helicases: 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.Electron Transport Complex IV: 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.Bacterial Proteins: Proteins found in any species of bacterium.Nuclear Proteins: 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.Protein Structure, Tertiary: 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.Intracellular Membranes: 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.Arabidopsis Proteins: 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.Arabidopsis: 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.Chloroplasts: 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.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Ribonucleoproteins, Small Nuclear: 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).Golgi Apparatus: 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)Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Phagosomes: 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.Organelle Size: The quantity of volume or surface area of ORGANELLES.Ribosome Subunits, Small, Eukaryotic: The small subunit of the 80s ribosome of eukaryotes. It is composed of the 18S RIBOSOMAL RNA and 32 different RIBOSOMAL PROTEINS.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Ribonucleoproteins, Small Nucleolar: Nucleolar RNA-protein complexes that function in pre-ribosomal RNA processing.Genetic Complementation Test: 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.Vacuoles: Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.RNA, Ribosomal, 18S: Constituent of the 40S subunit of eukaryotic ribosomes. 18S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.Fungal Proteins: Proteins found in any species of fungus.HeLa Cells: 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.Lysosomes: 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, Messenger: 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.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Gene Deletion: 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.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Microbodies: Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.Cell Line: Established cell cultures that have the potential to propagate indefinitely.RNA, Small Nucleolar: 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.Mitochondrial Size: The quantity of volume or surface area of MITOCHONDRIA.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Membrane Transport Proteins: 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.Cell Nucleus: 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)RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Multivesicular Bodies: 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.Coiled Bodies: A distinct subnuclear domain enriched in splicesomal snRNPs (RIBONUCLEOPROTEINS, SMALL NUCLEAR) and p80-coilin.Mitochondrial Membranes: 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).Escherichia coli: 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.Endosomes: Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.Multiprotein Complexes: Macromolecular complexes formed from the association of defined protein subunits.Microscopy, Electron, Transmission: Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.Cell Respiration: The metabolic process of all living cells (animal and plant) in which oxygen is used to provide a source of energy for the cell.Protein Processing, Post-Translational: 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.Biological Transport: 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.Gene Expression Regulation: 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, Electron: 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.RNA, Fungal: Ribonucleic acid in fungi having regulatory and catalytic roles as well as involvement in protein synthesis.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Secretory Vesicles: Vesicles derived from the GOLGI APPARATUS containing material to be released at the cell surface.Recombinant Fusion Proteins: 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.Adenosine Triphosphatases: 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.Protein Subunits: 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.Vesicular Transport Proteins: 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.Thylakoids: 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.Ribosome Subunits: 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.Cytoplasm: 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)Sequence Alignment: 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.Transport Vesicles: 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.Gene Expression Regulation, Fungal: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in fungi.RNA Transport: The process of moving specific RNA molecules from one cellular compartment or region to another by various sorting and transport mechanisms.Ribosome Subunits, Small, Bacterial: The small subunit of eubacterial RIBOSOMES. It is composed of the 16S RIBOSOMAL RNA and about 23 different RIBOSOMAL PROTEINS.Mitochondrial Membrane Transport Proteins: Proteins involved in the transport of specific substances across the membranes of the MITOCHONDRIA.Signal Transduction: 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.Autophagy: 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.Oxidative Phosphorylation: Electron transfer through the cytochrome system liberating free energy which is transformed into high-energy phosphate bonds.RNA Helicases: A family of proteins that promote unwinding of RNA during splicing and translation.Ribosome Subunits, Small: 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.Adaptor Protein Complex 3: An adaptor protein complex found primarily on perinuclear compartments.RNA: 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)ATP-Binding Cassette Transporters: 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.Pili, Sex: 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.Cytoplasmic Vesicles: Membrane-limited structures derived from the plasma membrane or various intracellular membranes which function in storage, transport or metabolism.Microscopy, Fluorescence: 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.rab GTP-Binding Proteins: A large family of MONOMERIC GTP-BINDING PROTEINS that play a key role in cellular secretory and endocytic pathways. EC 3.6.1.-.Sirtuin 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.Carbon-Sulfur Lyases: Enzymes that catalyze the cleavage of a carbon-sulfur bond by means other than hydrolysis or oxidation. EC 4.4.RNA, Ribosomal, 5.8S: Constituent of the 60S subunit of eukaryotic ribosomes. 5.8S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Cells, Cultured: 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.Green Fluorescent Proteins: 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.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Conserved Sequence: 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.Muscle, Skeletal: 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.Immunoblotting: 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.SMN Complex Proteins: 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, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Gene Expression Profiling: The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.Proteins: 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.Plastids: 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.Blotting, Western: 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, Mitochondrial: 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.Two-Hybrid System Techniques: 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.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.Genes, Fungal: The functional hereditary units of FUNGI.Pichia: Yeast-like ascomycetous fungi of the family Saccharomycetaceae, order SACCHAROMYCETALES isolated from exuded tree sap.Flagella: 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)Protein Folding: Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.Immunoprecipitation: 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.Active Transport, Cell Nucleus: Gated transport mechanisms by which proteins or RNA are moved across the NUCLEAR MEMBRANE.Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.HEK293 Cells: A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.Microscopy, Immunoelectron: 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.Cloning, Molecular: 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.Mitochondrial Proton-Translocating ATPases: 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.Lipid Metabolism: Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.DNA-Binding Proteins: 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.Protein Multimerization: The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.Energy Metabolism: The chemical reactions involved in the production and utilization of various forms of energy in cells.Gene Silencing: Interruption or suppression of the expression of a gene at transcriptional or translational levels.Methyltransferases: 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.Ribonucleoproteins: Complexes of RNA-binding proteins with ribonucleic acids (RNA).Cell Compartmentation: A partitioning within cells due to the selectively permeable membranes which enclose each of the separate parts, e.g., mitochondria, lysosomes, etc.trans-Golgi Network: 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.DNA Primers: 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.Citrate (si)-Synthase: 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 4.1.3.7.Periplasm: The space between the inner and outer membranes of a cell that is shared with the cell wall.Drosophila Proteins: 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.Mutant Proteins: Proteins produced from GENES that have acquired MUTATIONS.Mutagenesis, Insertional: 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.Chlorophyll: Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.Centrioles: 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.Genes, Bacterial: The functional hereditary units of BACTERIA.Reverse Transcriptase Polymerase Chain Reaction: 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.GTP Phosphohydrolases: Enzymes that hydrolyze GTP to GDP. EC 3.6.1.-.RNA-Induced Silencing Complex: 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).Mice, Knockout: 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.Mitochondria, Heart: The mitochondria of the myocardium.Subcellular Fractions: 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)Karyopherins: 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.Protein Sorting Signals: Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.Plasmids: 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.Gene Knockout Techniques: 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.Chromogranin A: 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.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Electron Transport Chain Complex Proteins: 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.Polyribosomes: 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)Eukaryotic Cells: Cells of the higher organisms, containing a true nucleus bounded by a nuclear membrane.Oxidation-Reduction: 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).Mitochondrial Diseases: 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.Cell Wall: 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.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.Oxygen Consumption: 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)AMP-Activated Protein Kinases: 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.Gene Knockdown Techniques: 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.Photosynthesis: 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)Eukaryotic Initiation Factors: 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.Endoribonucleases: 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.-.COP-Coated Vesicles: 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.RNA, Small Nuclear: 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.Protozoan Proteins: Proteins found in any species of protozoan.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Mutagenesis: Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.Adenosine Triphosphate: 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.

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)

*Biogenesis

... is the production of new living organisms or organelles. Conceptually, biogenesis is primarily attributed to Louis ... The term biogenesis was coined by Henry Charlton Bastian to mean the generation of a life form from nonliving materials, ... The term biogenesis may also refer to biochemical processes of production in living organisms (see biosynthesis). The Ancient ... ISBN 978-1-150-66769-5. The microbial world: a look at things small Biogenesis and Abiogenesis: Critiques and Addresses ...

*Mitochondrial biogenesis

... is the process by which cells increase their individual mitochondrial mass and copy number to increase ... Mitochondrial biogenesis is activated by numerous different signals during times of cellular stress or in response to ... PGC- 1β, a protein that is structurally similar to PGC-1α, is also involved in regulating mitochondrial biogenesis, but differs ... AMPK activation then continued to activate PGC- 1α and NRFs in these mice, and mitochondrial biogenesis was stimulated. The ...

*Ribosome biogenesis

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 prokaryotic cells, it 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 ...

*Biogenesis (disambiguation)

Biogenesis is the generation of life from existing life. Biogenesis may also refer to: "Biogenesis" (The X-Files) Biogenesis ... Mitochondrial biogenesis Organelle biogenesis Ribosome biogenesis Recapitulation theory, the biogenetic law of Ernst Haeckel ...

*Organelle biogenesis

... is the biogenesis, or creation, of cellular organelles in cells. Organelle biogenesis includes the process ... These may include mitochondrial biogenesis defects, peroxisome biogenesis disorders, and lysosomal storage disorders. Mullins, ... Christopher (2004). "Theory of Organelle Biogenesis: A Historical Perspective". The Biogenesis of Cellular Organelles. Springer ... Several processes are known to have developed for organelle biogenesis. These can range from de novo synthesis to the copying ...

*Biogenesis baseball scandal

The Biogenesis baseball scandal broke in 2013 when several Major League Baseball (MLB) players were accused of obtaining ... It then paid a former Biogenesis employee for documents. In April, Bosch received a complaint from the Florida Department of ... MLB conducted a large number of interviews with players it believed may be connected with Biogenesis in June. Every player ... On January 22, 2013, the Miami New Times obtained documents from former Biogenesis employee Porter Fisher which it said linked ...

*Peroxisomal biogenesis factor 2

... is a protein that in humans is encoded by the PEX2 gene. This gene encodes an integral ... 1996). "A unified nomenclature for peroxisome biogenesis factors". J. Cell Biol. 135 (1): 1-3. doi:10.1083/jcb.135.1.1. PMC ... 2005). "The PEX Gene Screen: molecular diagnosis of peroxisome biogenesis disorders in the Zellweger syndrome spectrum". Mol. ... GeneReviews/NCBI/NIH/UW entry on Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum OMIM entries on Peroxisome ...

*Peroxisomal biogenesis factor 11

... (PEX11) are peroxisomal membrane proteins which promote peroxisome division in eukaryotic ...

*Probable ribosome biogenesis protein RLP24

... is a protein that in humans is encoded by the RSL24D1 gene. This gene encodes a ...

*Ribosome biogenesis protein BRX1 homolog

... (BRIX1) also known as brix domain-containing protein 2 (BXDC2) is a protein that in ... 2002). "Brix from xenopus laevis and brx1p from yeast define a new family of proteins involved in the biogenesis of large ...

*Biogenesis of lysosome-related organelles complex 3

... has been shown to interact with Rab9A. The identified protein subunits of ... BLOC-3 or biogenesis of lysosome-related organelles complex 3 is a ubiquitously expressed multisubunit protein complex. ... Nazarian R, Falcón-Pérez JM, Dell'Angelica EC (July 2003). "Biogenesis of lysosome-related organelles complex 3 (BLOC-3): a ... "Assembly of the biogenesis of lysosome-related organelles complex-3 (BLOC-3) and its interaction with Rab9". J. Biol. Chem. 285 ...

*Biogenesis of lysosome-related organelles complex 1

BLOC-1 or biogenesis of lysosome-related organelles complex 1 is a ubiquitously expressed multisubunit protein complex. BLOC-1 ... a novel complex containing the pallidin and muted proteins involved in the biogenesis of melanosomes and platelet-dense ... is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet ...

*The X-Files Mythology, Volume 3 - Colonization

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 ...

*Diversitas

... a project aiming at exploring and understanding mountain biodiversity bioGENESIS - a project aiming at providing an ... ". "bioGENESIS". "bioDISCOVERY". "ecoSERVICES". "bioSUSTAINABILITY". "agroBIODIVERSITY". "ecoHEALTH". "freshwaterBIODIVERSITY ...

*List of guest appearances on The X-Files

Rob Bowman (director), Chris Carter & Frank Spotnitz (writers) (16 May 1999). "Biogenesis". The X-Files. Season 6. Episode 22. ... ", "Biogenesis", "The Sixth Extinction II: Amor Fati") Maggie Wheeler ("Born Again") Dana Wheeler-Nicholson ("Syzygy") Bernard ...

*Carotol

Parker, W.; Roberts, J.S (1967). "Sesquiterpene Biogenesis". Quart. Rev. 21 (3): 331-363. doi:10.1039/qr9672100331. ...

*Paul Nathaniel Temple Jr.

access-date= requires ,url= (help) "Paul N. Temple". BioGenesis Enterprises. Retrieved 2009-07-03. "Paul N. Temple". Institute ... is the Chairman Emeritus and co-founder of the Institute of Noetic Sciences and the Chairman of the Board of BioGenesis ...

*Gerontoplast

doi:10.1007/978-94-017-0247-8_4. "Transformation of Chloroplast to Gerontoplast" (PDF). Chloroplast Biogenesis: 155-242. doi: ... Biswal, Udaya; Mukesh, Raval (2003). "Transformation of Chloroplast to Gerontoplast". Chloroplast Biogenesis. Springer, ...

*Endomembrane system

However, although it is clear that lipid transport is a central process in organelle biogenesis, the mechanisms by which lipids ... Morre, D.J. (1975). "Membrane Biogenesis". Annual Review of Plant Physiology. 26 (1): 441-481. doi:10.1146/annurev.pp.26.060175 ... Voelker DR (1 December 1991). "Organelle biogenesis and intracellular lipid transport in eukaryotes". Microbiol. Rev. 55 (4): ...

*Peroxisome

Lazarow PB, Fujiki Y (1985). "Biogenesis of peroxisomes". Annual Review of Cell Biology. 1: 489-530. doi:10.1146/annurev.cb. ... Two common examples are X-linked adrenoleukodystrophy and peroxisome biogenesis disorders. PEX genes encode the protein ...

*Cocaine

doi:10.1016/0031-9422(88)87026-2. Leete E, Marion L, Sspenser ID (1954). "Biogenesis of hyoscyamine". Nature. 174 (4431): 650-1 ...

*Peroxisomal disorder

... 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 ... GeneReviews/NCBI/NIH/UW entry on Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum Peroxisomal disorders at the US ... Steinberg, S.; Dodt, G.; Raymond, G.; Braverman, N.; Moser, A.; Moser, H. (2006). "Peroxisome biogenesis disorders". Biochimica ...

*Mónica Bettencourt-Dias

Bettencourt-Dias, Mónica; Glover, David M (September 2009). "SnapShot: Centriole Biogenesis". Cell. 136 (1): 188.e1-188.e2. doi ...

*Proteasome

Krüger E, Kloetzel PM, Enenkel C (2001). "20S proteasome biogenesis". Biochimie. 83 (3-4): 289-93. doi:10.1016/S0300-9084(01) ...

*Infantile Refsum disease

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 ... The Global Foundation for Peroxisomal Disorders GeneReviews/NCBI/NIH/UW entry on Peroxisome Biogenesis Disorders, Zellweger ... "Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum". PMID 20301621. Krause, C.; Rosewich, H.; Gärtner, J. (2009). " ...
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 ...
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 ...
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. ...
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 ...
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 ...
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 ...
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 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...
... 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
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 ...
An artificial chemistry is a chemical-like system that usually consists of objects, called molecules, that interact according to rules resembling chemical reaction rules. Artificial chemistries are created and studied in order to understand fundamental properties of chemical systems, including prebiotic evolution, as well as for developing chemical computing systems. Artificial chemistry is a field within computer science wherein chemical reactions-often biochemical ones-are computer-simulated, yielding insights on evolution, self-assembly, and other biochemical phenomena. The field does not use actual chemicals, and should not be confused with either synthetic chemistry or computational chemistry. Rather, bits of information are used to represent the starting molecules, and the end products are examined along with the processes that led to them. The field originated in artificial life but has shown to be a versatile method with applications in many fields such as chemistry, economics, sociology ...
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 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
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.. ...
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 Rechenkraft.net e.V. non-profit organisation.. The Rechenkraft.net 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 ...
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 : nano.nature.com
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
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 ...
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A tandem combinatorial reaction of four acyclic, colorless compounds (two α-aminoketones and two diones; one polar and one nonpolar for each) in aqueous solution (30 mM each, 60 °C, pH 7, 24 h) containing lipid vesicles and with or without quinones and solar illumination affords a distribution of up to 538 p
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.
Presentation November 2008 on Systems Architecture, the methodological and conceptual background to Living Architecture & Protocell Architecture
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If it takes up space and has mass then it matters - actually it is matter. There are numerous terms that relate to the basic or fundamental unit of matter - the atom. ELEMENTS are pure substances which means that they consist of only one type of atom. A COMPOUND consists of two or more different kind of atoms or ions in definite proportions ...
Looking for online definition of chemical evolution in the Medical Dictionary? chemical evolution explanation free. What is chemical evolution? Meaning of chemical evolution medical term. What does chemical evolution mean?
Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Astronomy and Space Physics. Faculty of Science and Technology, Astronomical observatory. ...
How did life originate? And can scientists create life? These questions not only occupy the minds of scientists interested in the origin of life, but also researchers working with technology of the future.. If we can create artificial living systems, we may not only understand the origin of life - we can also revolutionize the future of technology.. Protocells are the simplest, most primitive living systems, you can think of. The oldest ancestor of life on Earth was a protocell, and when we see, what it eventually managed to evolve into, we understand why science is so fascinated with protocells. If science can create an artificial protocell, we get a very basic ingredient for creating more advanced artificial life.. However, creating an artificial protocell is far from simple, and so far no one has managed to do that. One of the challenges is to create the information strings that can be inherited by cell offspring, including protocells. Such information strings are like modern DNA or RNA ...
A new robotic system at Georgia Techs Center for Chemical Evolution could soon let scientists better simulate and analyze the chemical reactions of early Earth on the surface of real rocks to further test the theory that catalytic minerals on a meteorites surface could have jump-started lifes first chemical reactions.
Now, researchers working with that hypothesis have achieved a significant advancement toward understanding an evolutionary mystery - how components of RNA and DNA formed from chemicals present on early Earth before life existed.. In surprisingly simple laboratory reactions in water, under everyday conditions, they have produced what could be good candidates for missing links on the pathway to the code of life.. And when those components joined up, the result even looked like RNA.. As the researchers work progresses, it could reveal that much of the original chemistry that led to life arose not in fiery cataclysms and in scarce quantities, but abundantly and gradually on quiet, rain-swept dirt flats or lakeshore rocks lapped by waves.. In turn, their work could increase our understanding of the probability of lifes existence elsewhere in the universe.. The research from the NSF/NASA Center for Chemical Evolution, headquartered at the Georgia Institute of Technology, is generously funded through ...
Explain the difference between the morphological species concept and the biological species concept.. With the morphological species concept, individuals are grouped into species by appearance and professional judgment. Those individuals that appear similar to one another are considered one species. This concept was the origin of taxonomy. Criticisms of this method are that it is arbitrary and that it may not be able to discriminate, for example, when one species mimics another. The biological species concept defines a species as a group of actually or potentially interbreeding individuals who are reproductively isolated from other groups. Individuals must be able to produce successful fertile offspring. Shortcomings of this concept are that it cannot be used with fossils or spatially disconnected populations.. Potential Question ...
Teacher instructions such as: "students should go home with the understanding that a new paradigm of explaining lifes origins is emerging from the failed attempts of naturalistic scenarios. This new way of thinking is predicated upon the hypothesis that intelligent input is necessary for lifes origins." (Module 8, "Teacher Resources," Slide 3 ...
In conclusion, much elegant work has been done starting from activated mono-nucleotides. However, the prebiotic synthesis of a specific macromolecular sequence does not seem to be at hand, giving us the same problem we have with polypeptide sequences. Since there is no ascertained prebiotic pathway to their synthesis, it may be useful to try to conceive some working hypothesis. In order to do that, I would first like to consider a preliminary question about the proteins we have on our Earth: "Why these proteins … and not other ones?". Discussing this question can in fact give us some clue as to how orderly sequences might have originated. […] A grain of sand in the Sahara - This is indeed a central question in our world of proteins. How have they been selected out? There is a well-known arithmetic at the basis of this question, (see for example De Duve, 2002) which says that for a polypeptide chain with 100 residues, 20^100 different chains are in principle possible: a number so large that ...
The computer code, written in C++, hosts the DNA sequence of M.mycoides JCVI-syn1.0. At runtime it acts as follows: 1) Preparing the DNA sequence of M.mycoides JCVI-syn1.0 in the memory, (with slightly modified watermarks). 2) Encoding own file-content in base32. The base32 code is then encoded in JCVIs DNA-encoded alphabet. 3) This representation of its digital form is then copied to a watermark of the bacterias genome in memory. With this, a fully functional bacterial DNA sequence including the digital code is generated. 4) Next it searches for FASTA-files on the computer, which are text-based representations of DNA sequences, commonly used by many DNA sequence libraries. 5) For each FASTA-file, it replaces the original DNA with the bacterial DNA containing the digital form of the computer code. The code has a classical self-replication mechanism as well, to eventually end up on a computer in a microbiology-laboratory with the ability of creating DNA out of digital genomes (such as ...
The above-mentioned three examples in-dicate the intricate structure and operation of the cell. No one has any experience of a machine that developed without a design-ers plan and specifications: therefore its reasonable to consider the possibility that such complex arrangements came about by a preconceived design. Unfortunately, such commonsense conclusions have no place in the currently dominant theories about the evolution of life. Rather, the pro-ponents of chemical evolution struggle to manufacture alternative explanations that refer only to blind chance and the imper-sonal laws of physics.. The most common scenario portrayed by chemical-evolution theorists begins more than four billion years ago, when clouds of gases and dust are believed to have con-densed on the earths ancient surface and gradually formed the primal atmosphere. Activated by ultraviolet light and electric bolts, this primitive atmosphere is sup-posed to have spontaneously given birth to organic chemical compounds, ...
The new Scripps Research Institute study shows flu virus proteins in the act of self-replication. Shown here is the influenza virus, which encapsidates its RNA genome (green) with a viral nucleoprotein (blue); the influenza virus polymerase (orange) reads and copies the RNA genome. In the background is an image of influenza virus ribonucleoprotein complexes observed using cryo-electron microscopy.
[Pathogenic factors of mycoplasma].: Mycoplasmas are smallest organisms capable of self-replication and cause various diseases in human. Especially, Mycoplasma
The NASA DC-8 and P-3B aircraft flew within about a kilometer or less of each other on three occasions during the Transport and Chemical Evolution Over the Pacific (TRACE-P) campaign in order to intercompare similar measurements on the two aircraft. The first and last intercomparisons were in relatively remote marine environments during transits to and from Asia. The first began with a boundary layer measurement followed by an ascent to 3 km. The second set of intercomparisons was at a fixed altitude of about 5.2 km off the coast of Japan, also in relatively clean air. Finally, the third measurement began at 5.3 km and then descended into the boundary layer. A number of measurements were compared with the best agreement observed for the most abundant compounds such as CO2 and CH4 and with very good agreement for CO, O3, and j values. Other comparisons, including measurements of the same compounds on both aircraft and measurements of the same compound by two different instruments on the DC-8, varied over
One of the most famous experiments of all time, Miller-Urey, was even more successful than thought and could hold the key to lifes origin
Define prebiotic: of, relating to, or being chemical or environmental precursors of the origin of life; also : existing or … - prebiotic in a sentence
Recent experimental work in the field of synthetic protocell biology has shown that prebiotic vesicles are able to steal lipids from each other. This phenomenon is driven purely by asymmetries in the physical state or composition of the vesicle membranes, and, when lipid resource is limited, translates directly into competition amongst the vesicles. Such a scenario is interesting from an origins of life perspective because a rudimentary form of cell-level selection emerges. To sharpen intuition about possible mechanisms underlying this behaviour, experimental work must be complemented with theoretical modelling. The aim of this paper is to provide a coarse-grain mathematical model of protocell lipid competition. Our model is capable of reproducing, often quantitatively, results from core experimental papers that reported distinct types vesicle competition. Additionally, we make some predictions untested in the lab, and develop a general numerical method for quickly solving the equilibrium ...
TY - JOUR. T1 - Collaboration between primitive cell membranes and soluble catalysts. AU - Adamala, Katarzyna P.. AU - Engelhart, Aaron E.. AU - Szostak, Jack W.. PY - 2016/3/21. Y1 - 2016/3/21. N2 - One widely held model of early life suggests primitive cells consisted of simple RNA-based catalysts within lipid compartments. One possible selective advantage conferred by an encapsulated catalyst is stabilization of the compartment, resulting from catalyst-promoted synthesis of key membrane components. Here we show model protocell vesicles containing an encapsulated enzyme that promotes the synthesis of simple fatty acid derivatives become stabilized to Mg 2+, which is required for ribozyme activity and RNA synthesis. Thus, protocells capable of such catalytic transformations would have enjoyed a selective advantage over other protocells in high Mg 2+ environments. The synthetic transformation requires both the catalyst and vesicles that solubilize the water-insoluble precursor lipid. We suggest ...
A team of researchers at Harvard University have modeled in the laboratory a primitive cell, or protocell, that is capable of building, copying and containing DNA.
Definition of Prebiotic: A prebiotic is a nondigestible food ingredient that beneficially affects the host by selectively stimulating the growth, activity or
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The first recent major use of this concept by a scholar, in Mystery of Lifes Origin (1984) by Charles Thaxton, compared operations science (plural) with origins science, which is one type of historical science, or perhaps is a narrow way to view historical science. Logically, we could call it either operations science (because different areas of science study the many different operations of nature) or operation science (if we view the many operations as being combined into a unified overall operation of nature). A prominent young-earth organization, Answers in Genesis, calls it operation science. But in his recent book Signature in the Cell (2009), Stephen Meyer follows Thaxton in calling it operations science. Originally I also used Thaxtons term and called it operations science, but I recently changed it to operation science, partly because in a recent Google-search in 2010, I found 300 entries for one search [operation science historical science] but only 80 when using the analogous ...
The DNA of the nucleus is present in the form of chromosomes. Structural studies on chromosomes have recently been reviewed by Ris (1967). Each chromosome represents a large amount of genetic information since it contains many times the DNA of the bacterial genome. , those in the nucleated red cells of birds) are unfolded, they are seen to be made up of fibers some 250 A thick. These fibers can be further disrupted into fibrils 60-100 A thick and composed of a central double helix of DNA with a protein coat, the DNA molecule being much folded on itself within the fibril. Jacob and Monod, 1961). In fact, Gilbert and Muller-Hill (1966) have identified the product of the i gene chemi- cally to be a protein. From Escherichia coli they isolated a protein fraction that had a high affinity for the lac inducer molecule isopropylβ-D-thiogalactoside; E. coli mutants lacking the i gene did not yield this protein. The protein was found to have a molecular weight of about 150,000-200,000. A similar ...
Technology Networks is an internationally recognised publisher that provides access to the latest scientific news, products, research, videos and posters.
Technology Networks is an internationally recognised publisher that provides access to the latest scientific news, products, research, videos and posters.
The invention relates to medicine, hepatology and pharmacology and can be used for producing and using a pharmaceutical composition based on a hepatoprotector and a prebiotic for treating and preventi
Buy Gallinée Prebiotic Foaming Facial Cleanser 120ml , luxury hair care, skincare and cosmetics at HQHair.com, with Free Delivery.
I could not be more pleased than to finally tell you about this, available soon, exclusively through FreeTheAnimal.com. Its Tribal Prebiotic.
When I got sick, the doctors sent samples to the Federal health authorities for testing. I saw a copy of the report. It said, What the hell is this? written off on one side of the report. Viruses have to go dormant and then mutate in order to flourish. They are the nearest life form on earth to the classic go to infinity, fast model that I talk about all the time. This is rather funny because viruses are one of the oldest life forms if not the oldest. They prefer non-oxygen environments and when mutations in the early earth waters created photosynthesis organisms, these multiplied very rapidly, pushing hard on the viral community ...
Despite "decades of persistent failure to create life by the spark in the soup method,"1 evolutionary biochemists are still trying to find an exclusively naturalistic explanation for how the first cell developed. Many possible chemical precursors to life have been systematically ruled out by rigorous experiments. What they have found is that the molecules necessary for life are found exclusively within cells that are already living.. One explanation proposed by evolutionists was the "RNA world" hypothesis, which holds that the first molecules to have spontaneously materialized in an ancient chemical soup were RNAs.2 This has met with too many obstacles to remain viable, so an embellishment to the RNA world was recently proposed by Thomas Cech in the journal Cell.3 He suggested that the first molecules to evolve toward life were ribonucleoproteins (RNPs), molecules made partly of RNA and partly of protein.. In nature, RNPs are found only inside cells. They have specific shapes, sizes, and ...
Many experiments have indicated that the conditions of the early earth were ideal for the spontaneous formation of biological compounds and perhaps even the first life forms, but as you said that really has little or nothing to do with evolution itself. Evoution is very well-supported by evidence and there are no serious scientific theories that contradict it, so the answer to your question is that its pretty solid ...
If I were asked so summarize life on Earth, the phrase variation on a theme seems appropriate. So many very different species share so much in common....
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A window into the mantle: analyzing the geochemistry of melt inclusions from the volcanic island of Mangaia. . 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.
In addition, Quzu supplies energies increasing cellular life force by instructing the body to optimize cellular vibrations per minute. According to Dr. Bryon Gentry, author of "Miracles of the Mind", optimal vibrations per minute for health are 108,000. To improve poor health, much higher vibrations are needed. Quzu encourages life force vibrations up to 400,000 vpm., enabling the immune system to work even better ...
Observations of cellular life in a local marsh lead researchers to the discovery of a new type of intercellular communication. Crouching in the boot-sucking mud of the Baylands Nature Preserve in Palo Alto, Manu Prakash, associate professor of...
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1] We use observations from two aircraft during the ICARTT campaign over the eastern United States and North Atlantic during summer 2004, interpreted with a global 3-D model of tropospheric chemistry (GEOS-Chem) to test current understanding of regional sources, chemical evolution, and export of NOx. The boundary layer NOx data provide top-down verification of a 50% decrease in power plant and industry NOx emissions over the eastern United States between 1999 and 2004. Observed NOx concentrations at 8-12 km altitude were 0.55 ± 0.36 ppbv, much larger than in previous U.S. aircraft campaigns (ELCHEM, SUCCESS, SONEX) though consistent with data from the NOXAR program aboard commercial aircraft. We show that regional lightning is the dominant source of this upper tropospheric NOx and increases upper tropospheric ozone by 10 ppbv. Simulating ICARTT upper tropospheric NOx observations with GEOS-Chem requires a factor of 4 increase in modeled NOx yield per flash (to 500 mol/flash). Observed OH ...
The word "evolution" is generally taken to mean biological evolution. However, biological evolution is simply the natural consequence of cosmic, stellar, geological, and chemical evolution. "From Chaos to Consciousness: A Brief History of the Universe" is the story of human evolution in this broader sense of the word. It is a textbook intended for a one-semester course in Astronomy and, after a few introductory chapters on the history of astronomy and the present universe, is narrowly focused on material directly and chronologically related to the eventual rise of conscious beings in the universe.. ...
Brett Smith for redOrbit.com - Your Universe Online. [ Watch the Video: Stanley Millers Forgotten Experiments, Analyzed ]. In a tribute to his old mentor and colleague, a marine chemistry professor at the University of California, San Diego was able to successfully replicate a mysterious and groundbreaking experiment by the "Father of Pre-biotic Chemistry.". In 1953, chemist Stanley Miller published a report on a landmark experiment that showed how peptides, basic building blocks of life, could have formed in the oceans of the early Earth. The experiment was unusual in that Miller made the head-scratching decision to use the chemical cyanamide, which may or may not have been available on the early Earth.. According to a newly published report in the journal Angewandte Chemie, Millers old student and colleague Jeffrey Bada, along with a team of American researchers, were able to replicate the old experiment using modern technology. The team was also able to show that the reaction could have ...
A mechanism for creating enantiomerism in the amino acids, the building blocks of the proteins, that involves global selection of one chirality by interactions between the amino acids and neutrinos from core-collapse supernovae is described. The selection involves the dependence of the interaction cross sections on the orientations of the spins of the neutrinos and the 14N nuclei in the amino acids, or in precursor molecules, which in turn couple to the molecular chirality. The subsequent chemical evolution and galactic mixing would ultimately populate the Galaxy with the selected species. The resulting amino acids could either be the source thereof on Earth, or could have triggered the chirality that was ultimately achieved for Earths amino acids.
The source of new beta-cells in adult human pancreas remains incompletely elucidated with recent studies in rodents providing evidence for neogenesis from progenitor cells in addition to self-replication. The aim of this study was to investigate expression of pluripotency-associated stem cell markers in proliferative cultures derived from adult human pancreas.Human pancreatic tissue was obtained from deceased donors following ethical approval and relative consent. Islet-enriched fraction was separated from the retrieved organ by digestion and density gradient centrifugation. Dissociated cells were seeded in adherent culture forming proliferative islet survivor cells(ISCs). These were characterized at fifth passage by RT-PCR, immunofluorescence staining, FACS, Western blot and transfection studies with an OCT4 promoter-driven reporter.Nuclear expression of the pluripotency-associated stem cell marker complex OCT4 / SOX2 / NANOG was confirmed in ISCs. The phenotype constituted approximately 8% ...
A golden age of a global family tree of life on Earth is upon us now with the widespread use of next-generation DNA sequencing generating millions of sequence data. A next generation TimeTree web can now help make it easier for people to make sense of much of that data. Imagine the history of life on Earth at your fingertips combined with the power to quickly cull five decades worth of all the evolutionary sequencing data and embedded geological studies.
The detection of complex cyanides in the protoplanetary disk around the young star MWC 480, and the similarity of their abundance ratios to those found in comets, implies that the rich organic chemistry of our solar nebula was not unique. The idea that comets once seeded the early Earth with the water and organics needed for life to originate has been widely discussed. This raises the question of whether the composition of comets - a reliable indicator of the composition of the solar nebula - is unique to the Solar System or commonly accompanies planet formation. Here Karin Öberg et al. report the detection of cyanides - CH3CN, HC3N and HCN - in the protoplanetary disk around the young star MWC 480, an analogue to the solar nebula. The abundance ratios of these nitrogen-bearing organics in the gas-phase are similar to those in comets, implying that complex organics accompany simpler volatiles in protoplanetary disks, and that the prebiotic chemistry present in the young Solar System is not unique.

A Drosophila model for the Zellweger spectrum of peroxisome biogenesis disorders | Disease Models & MechanismsA Drosophila model for the Zellweger spectrum of peroxisome biogenesis disorders | Disease Models & Mechanisms

A Drosophila model for the Zellweger spectrum of peroxisome biogenesis disorders. Fred D. Mast, Jing Li, Maninder K. Virk, ... A Drosophila model for the Zellweger spectrum of peroxisome biogenesis disorders. Fred D. Mast, Jing Li, Maninder K. Virk, ... A Drosophila model for the Zellweger spectrum of peroxisome biogenesis disorders. Fred D. Mast, Jing Li, Maninder K. Virk, ... Mutation of the PEX1 gene is the most common cause of peroxisome biogenesis disorders and is one of the causes of the most ...
more infohttp://dmm.biologists.org/content/early/2011/06/10/dmm.007419

The peroxin Pex6p gene is impaired in peroxisomal biogenesis disorders of complementation group 6<...The peroxin Pex6p gene is impaired in peroxisomal biogenesis disorders of complementation group 6<...

The peroxin Pex6p gene is impaired in peroxisomal biogenesis disorders of complementation group 6. Journal of Human Genetics. ... The peroxin Pex6p gene is impaired in peroxisomal biogenesis disorders of complementation group 6. / Matsumoto, N.; Tamura, S. ... Human genetic peroxisomal biogenesis disorders (PBDs), such as Zellweger syndrome, comprise 13 different complementation groups ... title = "The peroxin Pex6p gene is impaired in peroxisomal biogenesis disorders of complementation group 6", ...
more infohttps://jhu.pure.elsevier.com/en/publications/the-peroxin-pex6p-gene-is-impaired-in-peroxisomal-biogenesis-diso-3

Centriole Biogenesis: Polo-like Kinase as a vital factor? | MigrationsCentriole Biogenesis: Polo-like Kinase as a vital factor? | Migrations

Plk4-Induced Centriole Biogenesis in Human Cells [Dev Cell. 2007 Aug;13(2):190-202]. From the introduction: We have previously ... Ive been reading up on centriole biogenesis and centrosome duplication - look for more posts from myself on topics such as ... Centriole Biogenesis: Polo-like Kinase as a vital factor?. Ive been reading up on centriole biogenesis and centrosome ... centriole biogenesis, which is the process by which the single centrosome of quiescent cells duplicates and sets up chromosome ...
more infohttps://migration.wordpress.com/2007/08/23/centriole-biogenesis-polo-like-kinase-as-a-vital-factor/

Novel PEX1 mutations and genotype-phenotype correlations in Australasian peroxisome biogenesis disorder patientsNovel PEX1 mutations and genotype-phenotype correlations in Australasian peroxisome biogenesis disorder patients

The peroxisome biogenesis disorders (PBDs) are a group of neuronal migration/neurodegenerative disorders that arise from ... Novel PEX1 mutations and genotype-phenotype correlations in Australasian peroxisome biogenesis disorder patients. ...
more infohttps://research-repository.griffith.edu.au/handle/10072/16658

Biogenesis | biology | Britannica.comBiogenesis | biology | Britannica.com

... 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 ...
more infohttps://www.britannica.com/science/biogenesis

Peroxisome Biogenesis | SpringerLinkPeroxisome Biogenesis | SpringerLink

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 ...
more infohttps://link.springer.com/chapter/10.1007%2F978-981-15-1169-1_2

Biogenesis: Framed Prints | RedbubbleBiogenesis: Framed Prints | Redbubble

High quality Biogenesis inspired Framed Prints by independent artists and designers from around the world. We sell Framed ... High quality Biogenesis inspired Framed Prints by independent artists and designers from around the world. We sell Framed ...
more infohttps://www.redbubble.com/shop/biogenesis+framed-prints?ref=work_taglist

Cilium biogenesis/degradationCilium biogenesis/degradation

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 ...
more infohttps://www.uniprot.org/keywords/KW-0970

ribosome biogenesis | SGDribosome biogenesis | SGD

Gene Ontology Term: ribosome biogenesis. GO ID. GO:0042254 Aspect. Biological Process. Description. A cellular process that ... ribosome biogenesis and assembly View GO Annotations in other species in AmiGO ...
more infohttps://www.yeastgenome.org/go/GO:0042254

Amazon.com: Biogenesis eBook: Tatsuaki Ishiguro: Kindle StoreAmazon.com: Biogenesis eBook: Tatsuaki Ishiguro: Kindle Store

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 ...
more infohttps://www.amazon.com/Biogenesis-Tatsuaki-Ishiguro-ebook/dp/B00ZNG4MA0

Sesquiterpene Lactones: Biogenesis and Biomimetic Transformations | SpringerLinkSesquiterpene Lactones: Biogenesis and Biomimetic Transformations | SpringerLink

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 ...
more infohttps://link.springer.com/chapter/10.1007%2F978-1-4684-8789-3_4

Biogenesis Ltd Company ProfileBiogenesis Ltd Company Profile

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 ...
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protein complex biogenesis | SGDprotein complex biogenesis | SGD

Gene Ontology Term: protein complex biogenesis. GO ID. GO:0070271 Aspect. Biological Process. Description. A cellular process ... protein complex biogenesis and assembly View GO Annotations in other species in AmiGO ...
more infohttps://www.yeastgenome.org/go/GO:0070271

Ribosome biogenesis protein BRX1 (IPR026532) | InterPro | EMBL-EBIRibosome biogenesis protein BRX1 (IPR026532) | InterPro | EMBL-EBI

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]. ...
more infohttp://www.ebi.ac.uk/interpro/entry/IPR026532

Biogenesis of bacterial membrane vesicles.  - PubMed - NCBIBiogenesis of bacterial membrane vesicles. - PubMed - NCBI

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 ...
more infohttps://www.ncbi.nlm.nih.gov/pubmed/19432795?dopt=Abstract

MicroRNA-Biogenesis and Pre-mRNA Splicing CrosstalkMicroRNA-Biogenesis and Pre-mRNA Splicing Crosstalk

... 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 ...
more infohttps://www.hindawi.com/journals/bmri/2009/594678/

Autoproteolysis in hedgehog protein biogenesis | ScienceAutoproteolysis in hedgehog protein biogenesis | Science

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. ...
more infohttps://science.sciencemag.org/content/266/5190/1528?ijkey=d3fb91e32dec438ff4309c01a733c25cbc7e3490&keytype2=tf_ipsecsha

Biogenesis of America Articles, Photos, and Videos - Sun SentinelBiogenesis of America Articles, Photos, and Videos - Sun Sentinel

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 ...
more infohttp://www.sun-sentinel.com/topic/health/healthcare/biogenesis-of-america-ORGHC00055-topic.html

Biogenesis of America Articles, Photos, and Videos - Chicago TribuneBiogenesis of America Articles, Photos, and Videos - Chicago Tribune

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, ...
more infohttp://www.chicagotribune.com/topic/health/healthcare/biogenesis-of-america-ORGHC00055-topic.html

Biogenesis Muscle Aid: uses & side-effects | PatientsLikeMeBiogenesis Muscle Aid: uses & side-effects | PatientsLikeMe

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- ...
more infohttps://www.patientslikeme.com/treatments/show/23555-biogenesis-muscle-aid-side-effects-and-efficacy

MicroRNAs: genomics, biogenesis, mechanism, and function.  - PubMed - NCBIMicroRNAs: genomics, biogenesis, mechanism, and function. - PubMed - NCBI

MicroRNAs: genomics, biogenesis, mechanism, and function.. Bartel DP1.. Author information. 1. Whitehead Institute for ...
more infohttps://www.ncbi.nlm.nih.gov/pubmed/14744438?dopt=Abstract

Structure and function of Zucchini endoribonuclease in piRNA biogenesis | NatureStructure and function of Zucchini endoribonuclease in piRNA biogenesis | Nature

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 ( ...
more infohttps://www.nature.com/articles/nature11509?error=cookies_not_supported&code=911970b6-7a01-4562-a341-a93119d65bdd

TFEB Links Autophagy to Lysosomal Biogenesis | ScienceTFEB Links Autophagy to Lysosomal Biogenesis | Science

TFEB Links Autophagy to Lysosomal Biogenesis. By Carmine Settembre, Chiara Di Malta, Vinicia Assunta Polito, Moises Garcia ... TFEB Links Autophagy to Lysosomal Biogenesis. By Carmine Settembre, Chiara Di Malta, Vinicia Assunta Polito, Moises Garcia ... A gene network regulating lysosomal biogenesis and function. Science 325, 473 (2009). pmid:19556463. ... The transcription factor EB (TFEB), a master gene for lysosomal biogenesis, coordinated this program by driving expression of ...
more infohttp://science.sciencemag.org/content/332/6036/1429?ijkey=603a23896ceeaa340afc72e880b08b5f91320ce7&keytype2=tf_ipsecsha

BioGenesis NutraceuticalsBioGenesis Nutraceuticals

While many product lines provide high-quality supplements, BioGenesis provides comprehensive, highly ... BioGenesis Nutraceuticals has been helping practitioners meet the nutritional needs of their patients for almost a decade. ... BioGenesis Nutraceuticals has been helping practitioners meet the nutritional needs of their patients for almost a decade. ... BioGenesis products simplify the prescription for the clinician and the patient for improved patient compliance and superior ...
more infohttps://www.goldenneedleonline.com/BioGenesis-Nutraceuticals/

Plk4-induced centriole biogenesis in human cells.Plk4-induced centriole biogenesis in human cells.

... 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. ...
more infohttp://www.uniprot.org/citations/17681131
  • Collectively, these data afford a comprehensive view of the assembly pathway underlying centriole biogenesis in human cells. (uniprot.org)
  • It is required for biogenesis of the 60S ribosomal subunit [ PMID: 11843177 ]. (ebi.ac.uk)
  • Brix from xenopus laevis and brx1p from yeast define a new family of proteins involved in the biogenesis of large ribosomal subunits. (ebi.ac.uk)
  • 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. (sun-sentinel.com)
  • 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. (sun-sentinel.com)
  • While many product lines provide high-quality supplements, BioGenesis provides comprehensive, highly concentrated, therapeutic products specifically targeted for your patients' needs. (goldenneedleonline.com)
  • At least two of these chasms exist due to the existence of the irrefutable, highly respected Law of Biogenesis, or Biogenic Law (Simmons, 2007). (apologeticspress.org)
  • We propose a model for piRNA biogenesis in animal germ lines, in which the Zuc endoribonuclease has a key role in primary piRNA maturation. (nature.com)
  • Therefore, achieving a balance between these mechanisms allow a cell to have the proper organization of its mitochondrial network during biogenesis and may have an important role in muscle adaptation to physiological stress. (wikipedia.org)
  • The term biogenesis was coined by Henry Charlton Bastian to mean the generation of a life form from nonliving materials, however, Thomas Henry Huxley chose the term abiogenesis and redefined biogenesis for life arising from preexisting life. (wikipedia.org)
  • BioGenesis products simplify the prescription for the clinician and the patient for improved patient compliance and superior clinical results. (goldenneedleonline.com)
  • BioGenesis Nutraceuticals has been helping practitioners meet the nutritional needs of their patients for almost a decade. (goldenneedleonline.com)
  • The synergistic properties of BioGenesis formulations allow your patients to benefit from a fewer number of capsules, making it easier to follow their treatment protocols. (goldenneedleonline.com)
  • Our ongoing commitment to quality products and services is demonstrated by our ISO 9001:2000 Quality Registration.Biogenesis, now a division of MorphoSys, is pleased to be able to bring new monoclonal antibodies developed using MorphoSys' HuCAL® Gold library to the diagnostic and research markets. (bioportfolio.com)
  • Whatever your antibody needs, Biogenesis is ready to provide the quality products and services that you can rely on. (bioportfolio.com)
  • These data support a model of MV biogenesis, wherein bacterial growth and division invoke temporary, localized reductions in the density of OM-PG and OM-PG-IM associations within the envelope structure, thus releasing OM as MVs. (nih.gov)
  • For more than 20 years, these customers have chosen Biogenesis for its quality, reliability, and innovation. (bioportfolio.com)
  • High quality Biogenesis inspired Framed Prints by independent artists and designers from around the world. (redbubble.com)
  • Biogenesis is his first work to appear in English. (amazon.com)
  • miRNAs are processed through a series of post-transcriptional biogenesis steps. (hindawi.com)
  • 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. (bioportfolio.com)
  • Biogenesis is a recognized leader in the supply of monoclonal and polyclonal antibodies and custom manufacturing services to IVD manufacturers, pharmaceutical companies and life science researchers ar. (bioportfolio.com)