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NCOA5
Nuclear receptor coactivator 5 (NCOA5), also known as coactivator independent of AF-2 function (CIA), is a protein that in humans is encoded by the ''NCOA5'' gene. Function This gene encodes a coregulator for the alpha and beta estrogen receptors and the orphan nuclear receptor Rev-ErbA beta. The protein localizes to the nucleus, and is thought to have both coactivator and corepressor In the field of molecular biology, a corepressor is a molecule that represses the expression of genes. In prokaryotes, corepressors are small molecules whereas in eukaryotes, corepressors are proteins. A corepressor does not directly bind to DNA, ... functions. Its interaction with nuclear receptors is independent of the AF2 domain on the receptors, which is known to regulate interaction with other coreceptors. Two alternatively spliced transcript variants for this gene have been described. However, the full length nature of one of the variants has not been determined. References Further r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Coregulators
In molecular biology and genetics, transcription coregulators are proteins that interact with transcription factors to either activate or repress the transcription of specific genes. Transcription coregulators that activate gene transcription are referred to as coactivators while those that repress are known as corepressors. The mechanism of action of transcription coregulators is to modify chromatin structure and thereby make the associated DNA more or less accessible to transcription. In humans several dozen to several hundred coregulators are known, depending on the level of confidence with which the characterisation of a protein as a coregulator can be made. One class of transcription coregulators modifies chromatin structure through covalent modification of histones. A second ATP dependent class modifies the conformation of chromatin. Histone acetyltransferases Nuclear DNA is normally tightly wrapped around histones rendering the DNA inaccessible to the general transc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrogen Receptor
Estrogen receptors (ERs) are a group of proteins found inside cells. They are receptors that are activated by the hormone estrogen (17β-estradiol). Two classes of ER exist: nuclear estrogen receptors ( ERα and ERβ), which are members of the nuclear receptor family of intracellular receptors, and membrane estrogen receptors (mERs) ( GPER (GPR30), ER-X, and Gq-mER), which are mostly G protein-coupled receptors. This article refers to the former (ER). Once activated by estrogen, the ER is able to translocate into the nucleus and bind to DNA to regulate the activity of different genes (i.e. it is a DNA-binding transcription factor). However, it also has additional functions independent of DNA binding. As hormone receptors for sex steroids ( steroid hormone receptors), ERs, androgen receptors (ARs), and progesterone receptors (PRs) are important in sexual maturation and gestation. Proteomics There are two different forms of the estrogen receptor, usually referred to as α ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rev-ErbA Beta
Rev-Erb beta (Rev-Erbβ), also known as nuclear receptor subfamily 1 group D member 2 (NR1D2), is a member of the Rev-Erb protein family. Rev-Erbβ, like Rev-Erbα, belongs to the nuclear receptor superfamily of transcription factors and can modulate gene expression through binding to gene promoters. Together with Rev-Erbα, Rev-Erbβ functions as a major regulator of the circadian clock. These two proteins are partially redundant. Current research suggests that Rev-Erbβ is less important in maintaining the circadian clock than Rev-Erbα; knock-out studies of Rev-Erbα result in significant circadian disruption but the same has not been found with Rev-Erbβ. Rev-Erbβ compensation for Rev-Erbα varies across tissues, and further research is needed to elucidate the separate role of Rev-Erbβ. This gene is expressed in the central and peripheral nervous system, spleen, mandibular maxillary processes, and blood islands. Rev-Erbβ plays a major role in the conduction of inductive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coactivator (genetics)
A coactivator is a type of transcriptional coregulator that binds to an activator (a transcription factor) to increase the rate of transcription of a gene or set of genes. The activator contains a DNA binding domain that binds either to a DNA promoter site or a specific DNA regulatory sequence called an enhancer. Binding of the activator-coactivator complex increases the speed of transcription by recruiting general transcription machinery to the promoter, therefore increasing gene expression. The use of activators and coactivators allows for highly specific expression of certain genes depending on cell type and developmental stage. Some coactivators also have histone acetyltransferase (HAT) activity. HATs form large multiprotein complexes that weaken the association of histones to DNA by acetylating the N-terminal histone tail. This provides more space for the transcription machinery to bind to the promoter, therefore increasing gene expression. Activators are found in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corepressor (genetics)
In the field of molecular biology, a corepressor is a molecule that represses the expression of genes. In prokaryotes, corepressors are small molecules whereas in eukaryotes, corepressors are proteins. A corepressor does not directly bind to DNA, but instead indirectly regulates gene expression by binding to repressors. A corepressor downregulates (or represses) the expression of genes by binding to and activating a repressor transcription factor. The repressor in turn binds to a gene's operator sequence (segment of DNA to which a transcription factor binds to regulate gene expression), thereby blocking transcription of that gene. Function Prokaryotes In prokaryotes, the term corepressor is used to denote the activating ligand of a repressor protein. For example, the '' E. coli'' tryptophan repressor (TrpR) is only able to bind to DNA and repress transcription of the ''trp'' operon when its corepressor tryptophan is bound to it. TrpR in the absence of tryptophan is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
