<unk>  is an epigenetic modification to the DNA packaging protein Histone H3. It is a mark that indicates the di-methylation at the 9th lysine residue of the histone H3 protein.<unk>  is strongly associated with transcriptional repression.<unk>  levels are higher at silent compared to active genes in a 10kb region surrounding the transcriptional start site.<unk>  represses gene expression both passively, by prohibiting acetylation and therefore binding of RNA polymerase or its regulatory factors, and actively, by recruiting transcriptional repressors.<unk>  has also been found in megabase blocks, termed Large Organised Chromatin K9 domains (LOCKS), which are primarily located within gene-sparse regions but also encompass genic and intergenic intervals. Its synthesis is catalyzed by G9a, G9a-like protein, and PRDM2.<unk>  can be removed by a wide range of histone lysine demethylases (KDMs) including KDM1, KDM3, KDM4 and KDM7 family members.<unk>  is important for various biological processes including cell lineage commitment, the reprogramming of somatic cells to induced pluripotent stem cells, regulation of the inflammatory response, and addiction to drug use.
H3K9me2
H3K9me3
H3K36me
H3K14ac
H4K8ac
H4K12ac
H4K5ac
H3K9ac