function:Variant histone H2A which replaces conventional H2A in a subset of nucleosomes. Nucleosomes wrap and compact DNA into chromatin , limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation , DNA repair , DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones , also called histone code , and nucleosome remodeling. May be involved in the formation of constitutive heterochromatin. May be required for chromosome segregation during cell division. ,mass spectrometry:Monoisotopic , not modified PubMed:16457589 ,PTM:Acetylated on Lys-5 , Lys-8 and Lys-12 during interphase. Acetylation disappears at mitosis. ,PTM:Monoubiquitination of Lys-122 gives a specific tag for epigenetic transcriptional repression. ,PTM:Not phosphorylated. ,similarity:Belongs to the histone H2A family. ,subunit:The nucleosome is a histone octamer containing two molecules each of H2A , H2B , H3 and H4 assembled in one H3-H4 heterotetramer and two H2A-H2B heterodimers. The octamer wraps approximately 147 bp of DNA. H2A or its variant H2AFZ forms an heterodimer with H2B. H2AFZ interacts with INCENP. ,
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