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P300-CBP Coactivator Family
The p300-CBP coactivator family in humans is composed of two closely related transcriptional co-activating proteins (or coactivators): #p300 (also called EP300 or E1A binding protein p300) # CBP (also known as CREB-binding protein or CREBBP) Both p300 and CBP interact with numerous transcription factors and act to increase the expression of their target genes. Protein structure p300 and CBP have similar structures. Both contain five protein interaction domains: the nuclear receptor interaction domain (RID), the KIX domain (CREB and MYB interaction domain), the cysteine/histidine regions (TAZ1/CH1 and TAZ2/CH3) and the interferon response binding domain (IBiD). The last four domains, KIX, TAZ1, TAZ2 and IBiD of p300, each bind tightly to a sequence spanning both transactivation domains 9aaTADs of transcription factor p53. In addition p300 and CBP each contain a protein or histone acetyltransferase (PAT/HAT) domain and a bromodomain that binds acetylated lysines and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EP300
Histone acetyltransferase p300 also known as p300 HAT or E1A-associated protein p300 (where E1A = adenovirus early region 1A) also known as EP300 or p300 is an enzyme that, in humans, is encoded by the ''EP300'' gene. It functions as histone acetyltransferase that regulates transcription of genes via chromatin remodeling by allowing histone proteins to wrap DNA less tightly. This enzyme plays an essential role in regulating cell growth and division, prompting cells to mature and assume specialized functions (differentiate), and preventing the growth of cancerous tumors. The p300 protein appears to be critical for normal development before and after birth. The EP300 gene is located on the long (q) arm of the human chromosome 22 at position 13.2. This gene encodes the adenovirus E1A-associated cellular p300 transcriptional co-activator protein. EP300 is closely related to another gene, CREB binding protein, which is found on human chromosome 16. Function p300 HAT funct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cysteine
Cysteine (; symbol Cys or C) is a semiessential proteinogenic amino acid with the chemical formula, formula . The thiol side chain in cysteine enables the formation of Disulfide, disulfide bonds, and often participates in enzymatic reactions as a nucleophile. Cysteine is chiral, but both D and L-cysteine are found in nature. LCysteine is a protein monomer in all biota, and D-cysteine acts as a signaling molecule in mammalian nervous systems. Cysteine is named after its discovery in urine, which comes from the urinary bladder or cyst, from Ancient Greek, Greek κύστις ''kýstis'', "bladder". The thiol is susceptible to oxidation to give the disulfide bond, disulfide derivative cystine, which serves an important structural role in many proteins. In this case, the symbol Cyx is sometimes used. The deprotonated form can generally be described by the symbol Cym as well. When used as a food additive, cysteine has the E number E920. Cysteine is Genetic code, encoded by the codo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enhancer (genetics)
In genetics, an enhancer is a short (50–1500 bp) region of DNA that can be bound by proteins ( activators) to increase the likelihood that transcription of a particular gene will occur. These proteins are usually referred to as transcription factors. Enhancers are ''cis''-acting. They can be located up to 1 Mbp (1,000,000 bp) away from the gene, upstream or downstream from the start site. There are hundreds of thousands of enhancers in the human genome. They are found in both prokaryotes and eukaryotes. Active enhancers typically get transcribed as enhancer or regulatory non-coding RNA, whose expression levels correlate with mRNA levels of target genes. The first discovery of a eukaryotic enhancer was in the immunoglobulin heavy chain gene in 1983. This enhancer, located in the large intron, provided an explanation for the transcriptional activation of rearranged Vh gene promoters while unrearranged Vh promoters remained inactive. Lately, enhancers have been shown to be in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptor Molecules
Signal transducing adaptor proteins (STAPs) are proteins that are accessory to main proteins in a signal transduction pathway. Adaptor proteins contain a variety of protein-binding modules that link protein-binding partners together and facilitate the creation of larger signaling complexes. These proteins tend to lack any intrinsic enzymatic activity themselves, instead mediating specific protein–protein interactions that drive the formation of protein complexes. Examples of adaptor proteins include MYD88, Grb2 and SHC1. Signaling components Much of the specificity of signal transduction depends on the recruitment of several signalling components such as protein kinases and G-protein GTPases into short-lived active complexes in response to an activating signal such as a growth factor binding to its receptor. Domains Adaptor proteins usually contain several domains within their structure (e.g., Src homology 2 (SH2) and SH3 domains) that allow specific interactions with several ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Polymerase II
RNA polymerase II (RNAP II and Pol II) is a Protein complex, multiprotein complex that Transcription (biology), transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA. It is one of the three RNA polymerase, RNAP enzymes found in the nucleus of eukaryote, eukaryotic cells. A 550 kDa complex of 12 subunits, RNAP II is the most studied type of RNA polymerase. A wide range of transcription factors are required for it to bind to upstream gene promoter (biology), promoters and begin transcription. Discovery Early studies suggested a minimum of two RNAPs: one which synthesized rRNA in the nucleolus, and one which synthesized other RNA in the nucleoplasm, part of the nucleus but outside the nucleolus. In 1969, biochemists Robert G. Roeder and William J. Rutter, William Rutter discovered there are total three distinct nuclear RNA polymerases, an additional RNAP that was responsible for transcription of some kind of RNA in the nucleoplasm. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promoter (biology)
In genetics, a promoter is a sequence of DNA to which proteins bind to initiate transcription (genetics), transcription of a single RNA transcript from the DNA downstream of the promoter. The RNA transcript may encode a protein (mRNA), or can have a function in and of itself, such as tRNA or rRNA. Promoters are located near the transcription start sites of genes, Upstream and downstream (DNA), upstream on the DNA (towards the Directionality (molecular biology)#5′-end, 5' region of the sense strand). Promoters can be about 100–1000 base pairs long, the sequence of which is highly dependent on the gene and product of transcription, type or class of RNA polymerase recruited to the site, and species of organism. Overview For transcription to take place, the enzyme that synthesizes RNA, known as RNA polymerase, must attach to the DNA near a gene. Promoters contain specific DNA sequences such as response elements that provide a secure initial binding site for RNA polymerase and for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromatin
Chromatin is a complex of DNA and protein found in eukaryote, eukaryotic cells. The primary function is to package long DNA molecules into more compact, denser structures. This prevents the strands from becoming tangled and also plays important roles in reinforcing the DNA during cell division, preventing DNA repair#DNA damage, DNA damage, and regulating gene expression and DNA replication. During mitosis and meiosis, chromatin facilitates proper segregation of the chromosomes in anaphase; the characteristic shapes of chromosomes visible during this stage are the result of DNA being coiled into highly condensed chromatin. The primary protein components of chromatin are histones. An octamer of two sets of four histone cores (Histone H2A, Histone H2B, Histone H3, and Histone H4) bind to DNA and function as "anchors" around which the strands are wound.Maeshima, K., Ide, S., & Babokhov, M. (2019). Dynamic chromatin organization without the 30 nm fiber. ''Current opinion in cell biolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Expression
Gene expression is the process (including its Regulation of gene expression, regulation) by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, proteins or non-coding RNA, and ultimately affect a phenotype. These products are often proteins, but in non-protein-coding genes such as Transfer RNA, transfer RNA (tRNA) and Small nuclear RNA, small nuclear RNA (snRNA), the product is a functional List of RNAs, non-coding RNA. The process of gene expression is used by all known life—eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and viruses—to generate the macromolecule, macromolecular machinery for life. In genetics, gene expression is the most fundamental level at which the genotype gives rise to the phenotype, ''i.e.'' observable trait. The genetic information stored in DNA represents the genotype, whereas the phenotype results from the "interpretation" of that informati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrinsically Unstructured Proteins
In molecular biology, an intrinsically disordered protein (IDP) is a protein that lacks a fixed or ordered three-dimensional structure, typically in the absence of its macromolecular interaction partners, such as other proteins or RNA. IDPs range from fully unstructured to partially structured and include random coil, molten globule-like aggregates, or flexible linkers in large multi- domain proteins. They are sometimes considered as a separate class of proteins along with globular, fibrous and membrane proteins. IDPs are a very large and functionally important class of proteins. They are most numerous in eukaryotes, with an estimated 30-40% of residues in the eukaryotic proteome located in disordered regions. Disorder is present in around 70% of proteins, either in the form of disordered tails or flexible linkers. Proteins can also be entirely disordered and lack a defined secondary and/or tertiary structure. Their discovery has disproved the idea that three-dimensional s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PHD Finger
The PHD finger was discovered in 1993 as a Cysteine, Cys4-Histidine, His-Cys3 motif in the plant homeodomain (hence PHD) proteins HAT3.1 in ''Arabidopsis'' and maize ZmHox1a. The PHD zinc finger motif resembles the metal binding RING domain (Cys3-His-Cys4) and FYVE domain. It occurs as a single finger, but often in clusters of two or three, and it also occurs together with other domains, such as the chromodomain and the bromodomain. Role in epigenetics The PHD finger, approximately 50-80 amino acids in length, is found in more than 100 human proteins. Several of the proteins it occurs in are found in the nucleus, and are involved in chromatin-mediated Regulation of gene expression, gene regulation. The PHD finger occurs in proteins such as the transcriptional co-activators EP300, p300 and CREB binding protein, CBP, Polycomb-group proteins, Polycomb-like protein (Pcl), Trithorax-group proteins like ASH1L, ASH2L and MLL (gene), MLL, the autoimmune regulator (AIRE), Mi-2 complex ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromodomain
A bromodomain is an approximately 110 amino acid protein domain that recognizes acetylated lysine residues, such as those on the ''N''-terminal tails of histones. Bromodomains, as the "readers" of lysine acetylation, are responsible in transducing the signal carried by acetylated lysine residues and translating it into various normal or abnormal phenotypes. Their affinity is higher for regions where multiple acetylation sites exist in proximity. This recognition is often a prerequisite for protein-histone association and chromatin remodeling. The domain itself adopts an all-α protein fold, a bundle of four alpha helices each separated by loop regions of variable lengths that form a hydrophobic pocket that recognizes the acetyl lysine. Discovery The bromodomain was identified as a novel structural motif by John W. Tamkun and colleagues studying the Drosophila gene ''Brahma''/''brm'', and showed sequence similarity to genes involved in transcriptional activation. The name "bromo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histone Acetyltransferase
Histone acetyltransferases (HATs) are enzymes that acetylation, acetylate conserved lysine amino acids on histone proteins by transferring an acetyl group from acetyl-CoA to form ε-N-acetyllysine, ε-''N''-acetyllysine. DNA is wrapped around histones, and, by transferring an acetyl group to the histones, genes can be turned on and off. In general, histone acetylation increases gene expression. In general, histone acetylation is linked to DNA transcription, transcriptional activation and associated with euchromatin. Euchromatin, which is less densely compact, allows transcription factors to bind more easily to regulatory sites on DNA, causing transcriptional activation. When it was first discovered, it was thought that acetylation of lysine neutralizes the positive electric charge, charge normally present, thus reducing affinity between histone and (negatively charged) DNA, which renders DNA more accessible to transcription factors. Research has emerged, since, to show that lys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
