Codon, Nonsense
An amino acid-specifying codon that has been converted to a stop codon (CODON, TERMINATOR) by mutation. Its occurance is abnormal causing premature termination of protein translation and results in production of truncated and non-functional proteins. A nonsense mutation is one that converts an amino acid-specific codon to a stop codon.
Nonsense Mediated mRNA Decay
RNA Stability
The extent to which an RNA molecule retains its structural integrity and resists degradation by RNASE, and base-catalyzed HYDROLYSIS, under changing in vivo or in vitro conditions.
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.
3' Untranslated Regions
The sequence at the 3' end of messenger RNA that does not code for product. This region contains transcription and translation regulating sequences.
RNA-Binding Proteins
Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.
Codon, Terminator
Any codon that signals the termination of genetic translation (TRANSLATION, GENETIC). PEPTIDE TERMINATION FACTORS bind to the stop codon and trigger the hydrolysis of the aminoacyl bond connecting the completed polypeptide to the tRNA. Terminator codons do not specify amino acids.
Protein Biosynthesis
Base Sequence
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.
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.-.
Heterogeneous-Nuclear Ribonucleoprotein D
A heterogeneous-nuclear ribonucleoprotein that has specificity for AU-rich elements found in the 3'-region of mRNA and may play a role in RNA stability. Several isoforms of hnRNP D protein have been found to occur due to alternative mRNA splicing (RNA SPLICING).
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.
Exoribonucleases
A family of enzymes that catalyze the exonucleolytic cleavage of RNA. It includes EC 3.1.13.-, EC 3.1.14.-, EC 3.1.15.-, and EC 3.1.16.-. EC 3.1.-
Cytoplasmic Structures
Components of the cytoplasm excluding the CYTOSOL.
RNA, Fungal
Frameshift Mutation
A type of mutation in which a number of NUCLEOTIDES deleted from or inserted into a protein coding sequence is not divisible by three, thereby causing an alteration in the READING FRAMES of the entire coding sequence downstream of the mutation. These mutations may be induced by certain types of MUTAGENS or may occur spontaneously.
Tristetraprolin
A ZINC FINGER MOTIF containing transcription factor that was originally identified as one of the IMMEDIATE-EARLY PROTEINS. It shuttles between the CYTOPLASM and the CELL NUCLEUS and is involved in destabilization of mRNAs for TUMOR NECROSIS FACTOR-ALPHA.
Exons
RNA Cap-Binding Proteins
Proteins that specifically bind to RNA CAPS and form nuclear cap binding protein complexes. In addition to stabilizing the 5' end of mRNAs, they serve a diverse array of functions such as enhancing mRNA transport out of the CELL NUCLEUS and regulating MRNA TRANSLATION in the CYTOPLASM.
Transcription, Genetic
Saccharomyces cerevisiae
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.
Peptide Chain Termination, Translational
A process of GENETIC TRANSLATION whereby the terminal amino acid is added to a lengthening polypeptide. This termination process is signaled from the MESSENGER RNA, by one of three termination codons (CODON, TERMINATOR) that immediately follows the last amino acid-specifying CODON.
Poly(A)-Binding Proteins
Butyrate Response Factor 1
A ZINC FINGER MOTIF containing immediate early protein that is closely related to TRISTETRAPROLIN. It interacts with and helps destabilize VASCULAR ENDOTHELIAL GROWTH FACTOR mRNA.
RNA Processing, Post-Transcriptional
Gene Expression Regulation
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)
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.
Suppression, Genetic
Mutation process that restores the wild-type PHENOTYPE in an organism possessing a mutationally altered GENOTYPE. The second "suppressor" mutation may be on a different gene, on the same gene but located at a distance from the site of the primary mutation, or in extrachromosomal genes (EXTRACHROMOSOMAL INHERITANCE).
Half-Life
Poly A
RNA Caps
Nucleic acid structures found on the 5' end of eukaryotic cellular and viral messenger RNA and some heterogeneous nuclear RNAs. These structures, which are positively charged, protect the above specified RNAs at their termini against attack by phosphatases and other nucleases and promote mRNA function at the level of initiation of translation. Analogs of the RNA caps (RNA CAP ANALOGS), which lack the positive charge, inhibit the initiation of protein synthesis.
Pedigree
RNA Splicing
Ribonucleases
AU Rich Elements
Blotting, Northern
Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.
Codon
A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).
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.
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)
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.
Alternative Splicing
A process whereby multiple RNA transcripts are generated from a single gene. Alternative splicing involves the splicing together of other possible sets of EXONS during the processing of some, but not all, transcripts of the gene. Thus a particular exon may be connected to any one of several alternative exons to form a mature RNA. The alternative forms of mature MESSENGER RNA produce PROTEIN ISOFORMS in which one part of the isoforms is common while the other parts are different.
Nuclear Cap-Binding Protein Complex
A heterodimeric protein complex of RNA cap-binding proteins, which binds with high affinity to the 5' MRNA CAP STRUCTURE in the CELL NUCLEUS. The complex contains two subunits, one of 80-kDa molecular weight and another of 20-kDa molecular weight.
Trans-Activators
Regulatory Sequences, Ribonucleic Acid
Sequences within RNA that regulate the processing, stability (RNA STABILITY) or translation (TRANSLATION, GENETIC) of RNA.
Phenotype
Poly(A)-Binding Protein I
A poly(A) binding protein that has a variety of functions such as mRNA stabilization and protection of RNA from nuclease activity. Although poly(A) binding protein I is considered a major cytoplasmic RNA-binding protein it is also found in the CELL NUCLEUS and may be involved in transport of mRNP particles.
Peptide Termination Factors
Proteins that are involved in the peptide chain termination reaction (PEPTIDE CHAIN TERMINATION, TRANSLATIONAL) on RIBOSOMES. They include codon-specific class-I release factors, which recognize stop signals (TERMINATOR CODON) in the MESSENGER RNA; and codon-nonspecific class-II release factors.
Polyadenylation
The addition of a tail of polyadenylic acid (POLY A) to the 3' end of mRNA (RNA, MESSENGER). Polyadenylation involves recognizing the processing site signal, (AAUAAA), and cleaving of the mRNA to create a 3' OH terminal end to which poly A polymerase (POLYNUCLEOTIDE ADENYLYLTRANSFERASE) adds 60-200 adenylate residues. The 3' end processing of some messenger RNAs, such as histone mRNA, is carried out by a different process that does not include the addition of poly A as described here.
Introns
Hu Paraneoplastic Encephalomyelitis Antigens
A family of RNA-binding proteins that are homologues of ELAV protein, Drosophila. They were initially identified in humans as the targets of autoantibodies in patients with PARANEOPLASTIC ENCEPHALOMYELITIS. They are thought to regulate GENE EXPRESSION at the post-transcriptional level.
Ribonucleoproteins
Gene Expression Regulation, Fungal
Globins
A superfamily of proteins containing the globin fold which is composed of 6-8 alpha helices arranged in a characterstic HEME enclosing structure.
DNA Primers
Mutation, Missense
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.
Alleles
Cells, Cultured
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.
Open Reading Frames
A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR).
Polymerase Chain Reaction
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
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.
RNA Splice Sites
Nucleotide sequences located at the ends of EXONS and recognized in pre-messenger RNA by SPLICEOSOMES. They are joined during the RNA SPLICING reaction, forming the junctions between exons.
Transcription Factors
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
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.
RNA, Bacterial
Point Mutation
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.
Ribosomes
Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.
DNA, Complementary
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)
Models, Biological
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)
Carrier Proteins
Transport proteins that carry specific substances in the blood or across cell membranes.
Transfection
The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.
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.
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.
Nucleic Acid Conformation
Exosome Multienzyme Ribonuclease Complex
Models, Genetic
Cycloheximide
5' Untranslated Regions
The sequence at the 5' end of the messenger RNA that does not code for product. This sequence contains the ribosome binding site and other transcription and translation regulating sequences.
RNA Transport
The process of moving specific RNA molecules from one cellular compartment or region to another by various sorting and transport mechanisms.
Genes, Reporter
Protein Synthesis Inhibitors
Compounds which inhibit the synthesis of proteins. They are usually ANTI-BACTERIAL AGENTS or toxins. Mechanism of the action of inhibition includes the interruption of peptide-chain elongation, the blocking the A site of ribosomes, the misreading of the genetic code or the prevention of the attachment of oligosaccharide side chains to glycoproteins.
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.
Homozygote
An individual in which both alleles at a given locus are identical.
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.
DNA-Binding Proteins
Polyribonucleotide Nucleotidyltransferase
Binding Sites
Down-Regulation
A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
Genes, Recessive
Genes that influence the PHENOTYPE only in the homozygous state.
Gene Deletion
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.
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.
Chromosome Mapping
Any method used for determining the location of and relative distances between genes on a chromosome.
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.
Dactinomycin
A compound composed of a two CYCLIC PEPTIDES attached to a phenoxazine that is derived from STREPTOMYCES parvullus. It binds to DNA and inhibits RNA synthesis (transcription), with chain elongation more sensitive than initiation, termination, or release. As a result of impaired mRNA production, protein synthesis also declines after dactinomycin therapy. (From AMA Drug Evaluations Annual, 1993, p2015)
Eukaryotic Initiation Factor-4A
A component of eukaryotic initiation factor 4F that as an RNA helicase involved in unwinding the secondary structure of the 5' UNTRANSLATED REGION of MRNA. The unwinding facilitates the binding of the 40S ribosomal subunit.
Sequence Analysis, DNA
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
DNA
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
beta-Globins
Members of the beta-globin family. In humans, they are encoded in a gene cluster on CHROMOSOME 11. They include epsilon-globin, gamma-globin, delta-globin and beta-globin. There is also a pseudogene of beta (theta-beta) in the gene cluster. Adult HEMOGLOBIN is comprised of two ALPHA-GLOBIN chains and two beta-globin chains.
Gene Expression Regulation, Enzymologic
Untranslated Regions
The parts of the messenger RNA sequence that do not code for product, i.e. the 5' UNTRANSLATED REGIONS and 3' UNTRANSLATED REGIONS.
Genes
HEK293 Cells
A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.
Recombinant Fusion Proteins
Heterozygote
An individual having different alleles at one or more loci regarding a specific character.
Codon, Initiator
A codon that directs initiation of protein translation (TRANSLATION, GENETIC) by stimulating the binding of initiator tRNA (RNA, TRANSFER, MET). In prokaryotes, the codons AUG or GUG can act as initiators while in eukaryotes, AUG is the only initiator codon.
Genetic Code
The meaning ascribed to the BASE SEQUENCE with respect to how it is translated into AMINO ACID SEQUENCE. The start, stop, and order of amino acids of a protein is specified by consecutive triplets of nucleotides called codons (CODON).
In Situ Hybridization
A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.
Promoter Regions, Genetic
DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.
Yeasts
A general term for single-celled rounded fungi that reproduce by budding. Brewers' and bakers' yeasts are SACCHAROMYCES CEREVISIAE; therapeutic dried yeast is YEAST, DRIED.
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.
Protein Isoforms
Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.
Triose-Phosphate Isomerase
Membrane Proteins
Recombinant Proteins
Proteins prepared by recombinant DNA technology.
Polymorphism, Single-Stranded Conformational
Variation in a population's DNA sequence that is detected by determining alterations in the conformation of denatured DNA fragments. Denatured DNA fragments are allowed to renature under conditions that prevent the formation of double-stranded DNA and allow secondary structure to form in single stranded fragments. These fragments are then run through polyacrylamide gels to detect variations in the secondary structure that is manifested as an alteration in migration through the gels.
Adaptor Proteins, Signal Transducing
A broad category of carrier proteins that play a role in SIGNAL TRANSDUCTION. They generally contain several modular domains, each of which having its own binding activity, and act by forming complexes with other intracellular-signaling molecules. Signal-transducing adaptor proteins lack enzyme activity, however their activity can be modulated by other signal-transducing enzymes
Polynucleotide Adenylyltransferase
An enzyme that catalyzes the synthesis of polyadenylic acid from ATP. May be due to the action of RNA polymerase (EC 2.7.7.6) or polynucleotide adenylyltransferase (EC 2.7.7.19). EC 2.7.7.19.
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.
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.
Phosphoglycerate Kinase
Genotype
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
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.
Mutagenesis, Site-Directed
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
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.
Tumor Cells, Cultured
Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.
Mutagenesis
Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.
Peptide Chain Initiation, Translational
A process of GENETIC TRANSLATION whereby the formation of a peptide chain is started. It includes assembly of the RIBOSOME components, the MESSENGER RNA coding for the polypeptide to be made, INITIATOR TRNA, and PEPTIDE INITIATION FACTORS; and placement of the first amino acid in the peptide chain. The details and components of this process are unique for prokaryotic protein biosynthesis and eukaryotic protein biosynthesis.
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.
Mammals
Fibroblasts
RNA Isoforms
The different gene transcripts generated from a single gene by RNA EDITING or ALTERNATIVE SPLICING of RNA PRECURSORS.
Temperature
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
mRNA Cleavage and Polyadenylation Factors
Factors that are involved in directing the cleavage and POLYADENYLATION of the of MESSENGER RNA near the site of the RNA 3' POLYADENYLATION SIGNALS.
Eukaryotic Cells
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.
Nucleic Acid Hybridization
Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)
Receptors, CCR4
COS Cells
CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CERCOPITHECUS AETHIOPS).)
Nucleocytoplasmic Transport Proteins
Proteins involved in the process of transporting molecules in and out the cell nucleus. Included here are: NUCLEOPORINS, which are membrane proteins that form the NUCLEAR PORE COMPLEX; KARYOPHERINS, which carry molecules through the nuclear pore complex; and proteins that play a direct role in the transport of karyopherin complexes through the nuclear pore complex.
Oligonucleotides
Polymers made up of a few (2-20) nucleotides. In molecular genetics, they refer to a short sequence synthesized to match a region where a mutation is known to occur, and then used as a probe (OLIGONUCLEOTIDE PROBES). (Dorland, 28th ed)
Conserved Sequence
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).
Gene Silencing
Ribosomal Proteins
Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.
Heterogeneous-Nuclear Ribonucleoproteins
A family of ribonucleoproteins that were originally found as proteins bound to nascent RNA transcripts in the form of ribonucleoprotein particles. Although considered ribonucleoproteins they are primarily classified by their protein component. They are involved in a variety of processes such as packaging of RNA and RNA TRANSPORT within the nucleus. A subset of heterogeneous-nuclear ribonucleoproteins are involved in additional functions such as nucleocytoplasmic transport (ACTIVE TRANSPORT, CELL NUCLEUS) of RNA and mRNA stability in the CYTOPLASM.
Oligonucleotide Array Sequence Analysis
Hybridization of a nucleic acid sample to a very large set of OLIGONUCLEOTIDE PROBES, which have been attached individually in columns and rows to a solid support, to determine a BASE SEQUENCE, or to detect variations in a gene sequence, GENE EXPRESSION, or for GENE MAPPING.
Cercopithecus aethiops
Immunoprecipitation
Eukaryotic Initiation Factor-3
A multisubunit eukaryotic initiation factor that contains at least 8 distinct polypeptides. It plays a role in recycling of ribosomal subunits to the site of transcription initiation by promoting the dissociation of non-translating ribosomal subunits. It also is involved in promoting the binding of a ternary complex of EUKARYOTIC INITIATION FACTOR-2; GTP; and INITIATOR TRNA to the 40S ribosomal subunit.
Phosphorylation
RNA, Transfer
The small RNA molecules, 73-80 nucleotides long, that function during translation (TRANSLATION, GENETIC) to align AMINO ACIDS at the RIBOSOMES in a sequence determined by the mRNA (RNA, MESSENGER). There are about 30 different transfer RNAs. Each recognizes a specific CODON set on the mRNA through its own ANTICODON and as aminoacyl tRNAs (RNA, TRANSFER, AMINO ACYL), each carries a specific amino acid to the ribosome to add to the elongating peptide chains.
Cell Line, Tumor
A cell line derived from cultured tumor cells.
Genes, Dominant
Genes that influence the PHENOTYPE both in the homozygous and the heterozygous state.
Nogalamycin
Rats, Sprague-Dawley
Luciferases
Enzymes that oxidize certain LUMINESCENT AGENTS to emit light (PHYSICAL LUMINESCENCE). The luciferases from different organisms have evolved differently so have different structures and substrates.
Liver
Caenorhabditis elegans
Repressor Proteins
Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.
Genes, Suppressor
Genes that have a suppressor allele or suppressor mutation (SUPPRESSION, GENETIC) which cancels the effect of a previous mutation, enabling the wild-type phenotype to be maintained or partially restored. For example, amber suppressors cancel the effect of an AMBER NONSENSE MUTATION.
Gene Expression Regulation, Bacterial
Gene Expression Regulation, Developmental
Models, Molecular
Oxadiazoles
Oxadiazoles are heterocyclic organic compounds consisting of a five-membered ring containing two carbon atoms, one nitrogen atom, and two oxygen atoms (one as a part of the oxadiazole ring and the other as a substituent or part of a larger molecule), which can exist in various isomeric forms and are known for their versatile biological activities, including anti-inflammatory, antiviral, antibacterial, and antitumor properties.
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.
Immunohistochemistry
Exome
That part of the genome that corresponds to the complete complement of EXONS of an organism or cell.
Genetic Complementation Test
Organ Specificity
Regulatory Sequences, Nucleic Acid
Nucleic acid sequences involved in regulating the expression of genes.
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.
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.
Ribonuclease III
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.
Adenine
A purine base and a fundamental unit of ADENINE NUCLEOTIDES.
Restriction Mapping
TATA-Binding Protein Associated Factors
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.
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.