Histone H3.Y

Primate-specific variant histone H3, which constitutes a core component of nucleosomes. Histone H3.Y-containing nucleosomes accumulate around transcription start sites and have flexible DNA ends, suggesting that they form relaxed chromatin that allows transcription factor access. Histone H1 binds less efficiently to histone H3.Y-containing 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 (Probable).