Histones are nuclear proteins that form octameric structures which bind DNA to form units of chromatin called nucleosomes. The family of histones—H2A, H2B, H3, and H4—are key players in gene regulation. They undergo a number of post-translational modifications (PTM) in response to various stimuli, including phosphorylation on serine and threonine residues and methylation on lysine residues. PTMs produce configural changes in histone proteins that may induce nucleosome remodeling and expose or hide DNA sequences from transcriptional complexes. Methylation occurs on histone H3 at lysine 4, 9, 27, 36, and 79 residues. Previous studies have reported that methylation of H3 lysine 9 provides a binding site for heterochromatin adaptor proteins (HP1) which are involved in the formation of heterochromatin and gene repression. Conversely,deacetylation of histone H3 lysine 9 is associated with gene-activating events. Often, it is the pattern of different modifications on several histone residues that alter chromatin, rather than modification of single residues.，官网链接：https://www.sigmaaldrich.cn/product/mm/mabe241 默克 科研、开发、生产。 作为生命科学行业的全球领先供应商，我们致力于为科研、生物技术开发和生产，以及制药药物疗法开发和生产提供各类解决方案和服务。

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