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NuA4 Histone Acetyltransferase Complex
The NuA4 histone acetyltransferase complex is a protein complex that has histone acetylase activity on chromatin, as well as ATPase, DNA helicase and structural DNA binding activities. The complex is thought to be involved in double-strand DNA break repair. Subunits of the human complex include HTATIP/TIP60, TRRAP, RUVBL1, RUVBL2, beta-actin and BAF53/ACTL6A. In yeast, the complex has 13 subunits, including the catalytic subunit Esa1 (homologous to human Tip60). Post-translational acetylation of the histone H4 N-terminal tail in chromatin has been associated with several nuclear processes including transcription (genetics), transcription. Purification and characterization of a native multi-subunit complex (NuA4) from yeast that acetylates nucleosomal histone H4 have been reported. NuA4 has an apparent molecular mass of 1.3 MDa. All four conserved Lysine, lysines of histone H4 can be acetylated by NuA4. The catalytic subunit of the complex has been identified as the product of ESA1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Complex
A protein complex or multiprotein complex is a group of two or more associated polypeptide chains. Protein complexes are distinct from multienzyme complexes, in which multiple catalytic domains are found in a single polypeptide chain. Protein complexes are a form of quaternary structure. Proteins in a protein complex are linked by non-covalent protein–protein interactions. These complexes are a cornerstone of many (if not most) biological processes. The cell is seen to be composed of modular supramolecular complexes, each of which performs an independent, discrete biological function. Through proximity, the speed and selectivity of binding interactions between enzymatic complex and substrates can be vastly improved, leading to higher cellular efficiency. Many of the techniques used to enter cells and isolate proteins are inherently disruptive to such large complexes, complicating the task of determining the components of a complex. Examples of protein complexes include the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta-actin
Beta-actin (human gene and protein abbreviation ''ACTB''/ACTB) is one of six different actin isoforms which have been identified in humans. This is one of the two nonmuscle cytoskeletal actins. Actins are highly conserved proteins that are involved in cell motility, structure and integrity. Alpha actins are a major constituent of the contractile apparatus. Interactions Beta-actin has been shown to interact with SPTBN2. In addition, RNA-binding protein Sam68 was found to interact with the mRNA encoding β-actin, which regulates the synaptic formation of the dendritic spines with its cytoskeletal components. Beta-actin has been shown to activate eNOS, thereby increasing NO production. An eight-amino acid motif (326-333) in eNOS has been shown to mediate the interaction between actin and eNOS. Clinical relevance Recurrent mutations in this gene have been associated to cases of diffuse large B-cell lymphoma. Applications Beta actin is often used in Western blotting as a ... [...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 residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoprecipitation
Immunoprecipitation (IP) is the technique of precipitating a protein antigen out of solution using an antibody that specifically binds to that particular protein. This process can be used to isolate and concentrate a particular protein from a sample containing many thousands of different proteins. Immunoprecipitation requires that the antibody be coupled to a solid substrate at some point in the procedure. Types Individual protein immunoprecipitation (IP) Involves using an antibody that is specific for a known protein to isolate that particular protein out of a solution containing many different proteins. These solutions will often be in the form of a crude lysate of a plant or animal tissue. Other sample types could be body fluids or other samples of biological origin. Protein complex immunoprecipitation (Co-IP) Immunoprecipitation of intact protein complexes (i.e. antigen along with any proteins or ligands that are bound to it) is known as co-immunoprecipitation (Co-I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −COO− form under biological conditions), and a side chain lysyl ((CH2)4NH2), classifying it as a basic, charged (at physiological pH), aliphatic amino acid. It is encoded by the codons AAA and AAG. Like almost all other amino acids, the α-carbon is chiral and lysine may refer to either enantiomer or a racemic mixture of both. For the purpose of this article, lysine will refer to the biologically active enantiomer L-lysine, where the α-carbon is in the ''S'' configuration. The human body cannot synthesize lysine. It is essential in humans and must therefore be obtained from the diet. In organisms that synthesise lysine, two main biosynthetic pathways exist, the diaminopimelate and α-aminoadipate pathways, which employ distinct e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription (genetics)
Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins are said to produce messenger RNA (mRNA). Other segments of DNA are copied into RNA molecules called non-coding RNAs (ncRNAs). mRNA comprises only 1–3% of total RNA samples. Less than 2% of the human genome can be transcribed into mRNA ( Human genome#Coding vs. noncoding DNA), while at least 80% of mammalian genomic DNA can be actively transcribed (in one or more types of cells), with the majority of this 80% considered to be ncRNA. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. Transcription proceeds in the following general steps: # RNA polymerase, together with one or more general transcription factors, binds to promoter DNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylation
: In organic chemistry, acetylation is an organic esterification reaction with acetic acid. It introduces an acetyl group into a chemical compound. Such compounds are termed ''acetate esters'' or simply '' acetates''. Deacetylation is the opposite reaction, the removal of an acetyl group from a chemical compound. Organic synthesis Acetate esters and acetamides are generally prepared by acetylations. Acetylations are often used in making C-acetyl bonds in Friedel-Crafts reactions. Carbanions and their equivalents are susceptible to acetylations. Acetylation reagents Many acetylations are achieved using these three reagents: * Acetic anhydride. This reagent is common in the laboratory; its use cogenerates acetic acid. *Acetyl chloride. This reagent is also common in the laboratory, but its use cogenerates hydrogen chloride, which can be undesirable. *Ketene. At one time acetic anhydride was prepared by the reaction of ketene with acetic acid: :H2C=C=O + CH3COOH -> (CH3CO)2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yeast
Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitute 1% of all described fungal species. Yeasts are unicellular organisms that evolved from multicellular ancestors, with some species having the ability to develop multicellular characteristics by forming strings of connected budding cells known as pseudohyphae or false hyphae. Yeast sizes vary greatly, depending on species and environment, typically measuring 3–4 µm in diameter, although some yeasts can grow to 40 µm in size. Most yeasts reproduce asexually by mitosis, and many do so by the asymmetric division process known as budding. With their single-celled growth habit, yeasts can be contrasted with molds, which grow hyphae. Fungal species that can take both forms (depending on temperature or other conditions) are ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RUVBL2
RuvB-like 2 (E. coli), also known as RUVBL2, is a human gene coding for a protein belonging to the AAA+ family of proteins. Function This gene encodes the second human homologue of the bacterial RuvB gene. Bacterial RuvB protein is a DNA helicase essential for homologous recombination and DNA double-strand break repair. However, the evidence for whether RUVBL2 has DNA helicase activity is contradictory. This gene is physically linked to the CGB/LHB gene cluster on chromosome 19q13.3, and is very close (55 nt) to the LHB gene, in the opposite orientation. Interactions RUVBL2 has been shown to interact with RuvB-like 1 RuvB-like 1 (E. coli), also known as RUVBL1 and TIP49, is a human gene. RUVBL1 can form a hexamer. The hexamer can form a dodecamer with RUVBL2 protein. Possesses single-stranded DNA-stimulated ATPase and ATP-dependent DNA helicase (3' to 5') activ ... and Activating transcription factor 2. References Further reading * * * * * * * * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histone
In biology, histones are highly basic proteins abundant in lysine and arginine residues that are found in eukaryotic cell nuclei. They act as spools around which DNA winds to create structural units called nucleosomes. Nucleosomes in turn are wrapped into 30-nanometer fibers that form tightly packed chromatin. Histones prevent DNA from becoming tangled and protect it from DNA damage. In addition, histones play important roles in gene regulation and DNA replication. Without histones, unwound DNA in chromosomes would be very long. For example, each human cell has about 1.8 meters of DNA if completely stretched out; however, when wound about histones, this length is reduced to about 90 micrometers (0.09 mm) of 30 nm diameter chromatin fibers. There are five families of histones which are designated H1/H5 (linker histones), H2, H3, and H4 (core histones). The nucleosome core is formed of two H2A-H2B dimers and a H3-H4 tetramer. The tight wrapping of DNA around histones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RUVBL1
RuvB-like 1 (E. coli), also known as RUVBL1 and TIP49, is a human gene. RUVBL1 can form a hexamer. The hexamer can form a dodecamer with RUVBL2 protein. Possesses single-stranded DNA-stimulated ATPase and ATP-dependent DNA helicase (3' to 5') activity; hexamerization is thought to be critical for ATP hydrolysis and adjacent subunits in the ring-like structure contribute to the ATPase activity. Interactions RuvB-like 1 has been shown to interact with: * ACTL6A, * Beta-catenin, * EP400, * Myc, and * RUVBL2 RuvB-like 2 (E. coli), also known as RUVBL2, is a human gene coding for a protein belonging to the AAA+ family of proteins. Function This gene encodes the second human homologue of the bacterial RuvB gene. Bacterial RuvB protein is a DNA helic .... References Further reading * * * * * * * * * * * * * * * * * * * {{Gene-3-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRRAP
Transformation/transcription domain-associated protein, also known as TRRAP, is a protein that in humans is encoded by the ''TRRAP'' gene. TRRAP belongs to the phosphatidylinositol 3-kinase-related kinase protein family. Function TRRAP is an adaptor protein, which is found in various multiprotein chromatin complexes with histone acetyltransferase activity (HAT), which in turn is responsible for epigenetic transcription activation. TRRAP has a central role in MYC (c-Myc) transcription activation, and also participates in cell transformation by MYC. It is required for p53/TP53-, E2F1-, and E2F4-mediated transcription activation. It is also involved in transcription activation mediated by the adenovirus E1A, a viral oncoprotein that deregulates transcription of key genes. TRRAP is also required for the mitotic checkpoint and normal cell cycle progression. The MRN complex (composed of MRE11, RAD50, and NBS1) is involved in the detection and repair of DNA double-strand breaks (DSBs) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
