| GCN5 Histone acetyltransferase | |||||||||
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| Identifiers | |||||||||
| EC no. | 2.3.1.48 | ||||||||
| CAS no. | 9054-51-7 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
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Histone acetyltransferases (HATs) are enzymes that acetylate conserved lysine amino acids on histone proteins by transferring an acetyl group from acetyl-CoA to form 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 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 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 lysine acetylation and other posttranslational modifications of histones generate binding sites for specific protein–protein interaction domains, such as the acetyllysine-binding bromodomain[citation needed]. Histone acetyltransferases can also acetylate non-histone proteins, such as nuclear receptors and other transcription factors to facilitate gene expression.
- ^ Wang Y, Guo Y, Liu K, Yin Z, Liu R, Xia Y, Tan L, Yang P, Lee J, et al. (December 6, 2017). "KAT2A coupled with the α-KGDH complex acts as a histone H3 succinyltransferase". Nature. 552 (7684): 273–277. Bibcode:2017Natur.552..273W. doi:10.1038/nature25003. PMC 5841452. PMID 29211711.