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Histone H3 is a critical component of the nucleosome, which is the basic unit of chromatin. It plays a vital role in the regulation of gene transcription and is subject to various post-translational modifications （PTMs） that affect chromatin structure and gene expression. The H3 family includes several variants, with H3.1, H3.2, and H3.3 being the most well-known. H3.1 and H3.2 are deposited during DNA replication, while H3.3 can be deposited independently of DNA replication and is incorporated throughout the cell cycle2. Post-translational modifications of Histone H3, particularly on the N- and C-terminal tails, can influence the interaction between histones and DNA, as well as with other chromatin factors. These modifications can either promote a relaxed chromatin state that allows gene transcription or lead to a condensed chromatin state that typically suppresses transcription.