HAT1
Description
The HAT1 (histone acetyltransferase 1) is a protein-coding gene located on chromosome 2.
Histone acetyltransferase 1, also known as HAT1, is an enzyme that, in humans, is encoded by the HAT1 gene.
== Function == The protein encoded by this gene is a type B histone acetyltransferase (HAT) that is involved in the rapid acetylation of newly synthesized cytoplasmic histones, which are, in turn, imported into the nucleus for de novo deposition onto nascent DNA chains. Histone acetylation, in particular, of histone H4, plays an important role in replication-dependent chromatin assembly. To be specific, this HAT can acetylate soluble but not nucleosomal histone H4 at lysines 5 and 12, and, to a lesser degree, histone H2A at lysine 5.
Histone acetyltransferase 1 (HAT1) is a type B histone acetyltransferase that plays a crucial role in various cellular processes, including cell cycle progression, glucose metabolism, histone production, and DNA damage repair. HAT1 coordinates histone production and acetylation by binding to the H4 promoter. It acetylates histone H4 at lysine 5 (H4K5ac) and lysine 12 (H4K12ac) and, to a lesser extent, histone H2A at lysine 5 (H2AK5ac). HAT1 drives H4 production through chromatin binding, supporting chromatin replication and acetylation. Due to the tight coupling of H4 gene transcription to the S phase, HAT1 plays a significant role in S-phase entry and progression. Additionally, HAT1 promotes homologous recombination in DNA repair by facilitating histone turnover and incorporating acetylated H3.3 at double-strand break sites. Furthermore, HAT1 acetylates other substrates, including chromatin-related proteins. It also acetylates RSAD2, mediating the interaction between ubiquitin ligase UBE4A and RSAD2, leading to RSAD2 ubiquitination and subsequent degradation.
HAT1 is also known as KAT1.
