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Histone Deacetylase 2
Histone deacetylase 2 (HDAC2) is an enzyme that in humans is encoded by the ''HDAC2'' gene. It belongs to the histone deacetylase class of enzymes responsible for the removal of acetyl groups from lysine residues at the N-terminal region of the core histones (H2A, H2B, H3, and H4). As such, it plays an important role in gene expression by facilitating the formation of transcription repressor complexes and for this reason is often considered an important target for cancer therapy. Though the functional role of the class to which HDAC2 belongs has been carefully studied, the mechanism by which HDAC2 interacts with histone deacetylases of other classes has yet to be elucidated. HDAC2 is broadly regulated by protein kinase 2 (CK2) and protein phosphatase 1 (PP1), but biochemical analysis suggests its regulation is more complex (evinced by the coexistence of HDAC1 and HDAC2 in three distinct protein complexes). Essentially, the mechanism by which HDAC2 is regulated is still unclear b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrosine Kinase
A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to the tyrosine residues of specific proteins inside a cell. It functions as an "on" or "off" switch in many cellular functions. Tyrosine kinases belong to a larger class of enzymes known as protein kinases which also attach phosphates to other amino acids such as serine and threonine. Phosphorylation of proteins by kinases is an important mechanism for communicating signals within a cell (signal transduction) and regulating cellular activity, such as cell division. Protein kinases can become mutated, stuck in the "on" position, and cause unregulated growth of the cell, which is a necessary step for the development of cancer. Therefore, kinase inhibitors, such as imatinib and osimertinib, are often effective cancer treatments. Most tyrosine kinases have an associated protein tyrosine phosphatase, which removes the phosphate group. Reaction Protein kinases are a group of enzymes that possess a catal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EED (protein)
Polycomb protein EED is a protein that in humans is encoded by the ''EED'' gene. Function Polycomb protein EED is a member of the Polycomb-group (PcG) family. PcG family members form multimeric protein complexes, which are involved in maintaining the transcriptional repressive state of genes over successive cell generations. This protein interacts with enhancer of zeste 2, the cytoplasmic tail of integrin β7, immunodeficiency virus type 1 (HIV-1) MA protein, and histone deacetylase proteins. This protein mediates repression of gene activity through histone deacetylation, and may act as a specific regulator of integrin function. Two transcript variants encoding distinct isoforms have been identified for this gene. Clinical significance In humans, a ''de-novo'' mutation in EED has been reported in an individual displaying symptoms similar to those of Weaver syndrome. Interactions EED has been shown to interact with: * EZH2, * HDAC1, * Histone deacetylase 2, * ITGB7, * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNMT1
DNA (cytosine-5)-methyltransferase 1 is an enzyme that catalyzes the transfer of methyl groups to specific CpG structures in DNA, a process called DNA methylation. In humans, it is encoded by the ''DNMT1'' gene. DNMT1 forms part of the family of DNA methyltransferase enzymes, which consists primarily of DNMT1, DNMT3A, and DNMT3B. Function This enzyme is responsible for maintaining DNA methylation, which ensures the fidelity of this epigenetic patterns across cell divisions. In line with this role, it has a strong preference towards methylating CpGs on hemimethylated DNA. However, Dnmt1 can catalyze de novo DNA methylation in specific genomic contexts, including transposable elements and paternal imprint control regions. Aberrant methylation patterns are associated with certain human tumors and developmental abnormalities. See also * DNA methyltransferase Interactions DNMT1 has been shown to interact with UHRF1,: * DMAP1, * DNMT3A * DNMT3B, * HDAC2, * PCNA, * RB1. and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHD4
Chromodomain-helicase-DNA-binding protein 4 is an enzyme that in humans is encoded by the ''CHD4'' gene. Function The product of this gene belongs to the SNF2/RAD54 helicase family. It represents the main component of the nucleosome remodeling and deacetylase complex and plays an important role in epigenetic transcriptional repression. Patients with dermatomyositis develop antibodies against this protein. Interactions CHD4 has been shown to interact with HDAC1, Histone deacetylase 2, MTA2, SATB1 and Ataxia telangiectasia and Rad3 related. Clinical Mutations in this gene have been associated with a condition known as Sifrim-Hitz-Weiss syndrome.Weiss K, Lazar HP, Kurolap A, Martinez AF, Paperna T, Cohen L, Smeland MF, Wallen S, Solveig H, Keren B, Terhal P, Irving M, Takaku M, Roberts JD, Petrovich RM, Schrier Vergano SA11,12, Kenney A11, Hove H13, DeChene E, Quinonez SC, Colin E, Ziegler A, Rumple M, Jain M, Monteil D, Roeder ER, Nugent K, van Haeringen A, Gambello M, Sant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHD3
Chromodomain-helicase-DNA-binding protein 3 is an enzyme that in humans is encoded by the ''CHD3'' gene. Function This gene encodes a member of the CHD family of proteins which are characterized by the presence of chromo (chromatin organization modifier) domains and SNF2-related helicase/ATPase domains. This protein is one of the components of a histone deacetylase complex referred to as the Mi-2/NuRD complex which participates in the remodeling of chromatin by deacetylating histones. Chromatin remodeling is essential for many processes including transcription. Autoantibodies against this protein are found in a subset of patients with dermatomyositis. Three alternatively spliced transcripts encoding different isoforms have been described. Mutations in CHD3 cause a neurodevelopmental syndrome (Snijders Blok-Campeau syndrome) with macrocephaly and impaired speech and language. Interactions CHD3 has been shown to interact with: * HDAC1, * Histone deacetylase 2 and * SERBP1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CDH1 (gene)
Cadherin-1 or Epithelial cadherin (E-cadherin), (not to be confused with the APC/C activator protein CDH1) is a protein that in humans is encoded by the ''CDH1'' gene. Mutations are correlated with gastric, breast, colorectal, thyroid, and ovarian cancers. CDH1 has also been designated as CD324 (cluster of differentiation 324). It is a tumor suppressor gene. History The discovery of cadherin cell-cell adhesion proteins is attributed to Masatoshi Takeichi, whose experience with adhering epithelial cells began in 1966. His work originally began by studying lens differentiation in chicken embryos at Nagoya University, where he explored how retinal cells regulate lens fiber differentiation. To do this, Takeichi initially collected media that had previously cultured neural retina cells (CM) and suspended lens epithelial cells in it. He observed that cells suspended in the CM media had delayed attachment compared to cells in his regular medium. His interest in cell adherence was sparke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CDC20
The cell division cycle protein 20 homolog is an essential regulator of cell division that is encoded by the ''CDC20'' gene in humans. To the best of current knowledge its most important function is to activate the anaphase promoting complex (APC/C), a large 11-13 subunit complex that initiates chromatid separation and entrance into anaphase. The APC/CCdc20 protein complex has two main downstream targets. Firstly, it targets securin for destruction, enabling the eventual destruction of cohesin and thus sister chromatid separation. It also targets S and M-phase (S/M) cyclins for destruction, which inactivates S/M cyclin-dependent kinases (Cdks) and allows the cell to exit from mitosis. A closely related protein, Cdc20homologue-1 (Cdh1) plays a complementary role in the cell cycle. CDC20 appears to act as a regulatory protein interacting with many other proteins at multiple points in the cell cycle. It is required for two microtubule-dependent processes: nuclear movement prior to an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BUB3
Mitotic checkpoint protein BUB3 is a protein that in humans is encoded by the ''BUB3'' gene. Bub3 is a protein involved with the regulation of the Spindle checkpoint, Spindle Assembly Checkpoint (SAC); though BUB3 is non-essential in yeast, it is essential in higher eukaryotes. As one of the checkpoint proteins, Bub3 delays the irreversible onset of anaphase through direction of kinetochore localization during prometaphase to achieve biorientation. In directing the kinetochore-microtubule interaction, this ensures the proper (and consequently, bioriented) attachment of the chromosomes prior to anaphase. Bub3 and its related proteins that form the Spindle Assembly Checkpoint (SAC) inhibit the action of the Anaphase-promoting complex, Anaphase Promoting Complex (APC), preventing early anaphase entry and mitotic exit; this serves as a mechanism for the fidelity of chromosomal segregation. Function Bub3 is a crucial component in the formation of the mitotic spindle assembly complex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ataxia Telangiectasia And Rad3 Related
Serine/threonine-protein kinase ATR also known as ataxia telangiectasia and Rad3-related protein (ATR) or FRAP-related protein 1 (FRP1) is an enzyme that, in humans, is encoded by the ''ATR'' gene. It is a large kinase of about 301.66 kDa. ATR belongs to the phosphatidylinositol 3-kinase-related kinase protein family. ATR is activated in response to single strand breaks, and works with ATM to ensure genome integrity. Function ATR is a serine/ threonine-specific protein kinase that is involved in sensing DNA damage and activating the DNA damage checkpoint, leading to cell cycle arrest in eukaryotes. ATR is activated in response to persistent single-stranded DNA, which is a common intermediate formed during DNA damage detection and repair. Single-stranded DNA occurs at stalled replication forks and as an intermediate in DNA repair pathways such as nucleotide excision repair and homologous recombination repair. ATR is activated during more persistent issues with DNA damage; w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upregulation
In the biological context of organisms' production of gene products, downregulation is the process by which a cell decreases the quantity of a cellular component, such as RNA or protein, in response to an external stimulus. The complementary process that involves increases of such components is called upregulation. An example of downregulation is the cellular decrease in the expression of a specific receptor in response to its increased activation by a molecule, such as a hormone or neurotransmitter, which reduces the cell's sensitivity to the molecule. This is an example of a locally acting (negative feedback) mechanism. An example of upregulation is the response of liver cells exposed to such xenobiotic molecules as dioxin. In this situation, the cells increase their production of cytochrome P450 enzymes, which in turn increases degradation of these dioxin molecules. Downregulation or upregulation of an RNA or protein may also arise by an epigenetic alteration. Such an epigene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
