N of nucleosomal histone H3K9 is necessary for the assembly of constitutive heterochromatin. Dimethylation and trimethylation of histone H3K9 (H3K9me2 me3) gives binding internet sites for the heterochromatin protein HP1, which recruits extra silencing elements and locks in the repressed state. As well as H3K9 methylation, dimethylation andMeMeMeMeMeHARTKYTARKSTGGKAPRKQLATKAARKSAPATGGVKKP2 4 8 9 17 2627KMeMeHSGRGKGGKGLGKGGAKRHRKVLRD3Fig. 2. Identified methylation internet sites (Me) on histones H3 and H4. Each and every histone mark occurred at every methylation web page is indicated to have a unique function.trimethylation of H3K27 (H3K27me2 me3), connected with transcriptional repression, are characteristically observed in Polycomb group target genes.(13) Furthermore, trimethylation of H4K20 (H4K20me3) is actually a hallmark of silenced heterochromatic regions, Ribocil whereas monomethylation and dimethylation of H4K20 (H4K20me1 me2) are involved in DNA replication and DNA harm repair.(14) On the contrary, trimethylation of H3K36 (H3K36me3) was enriched via coding regions, peaking close to the 30 -ends of transcription units, which can be thought to become related with transcriptional elongation.(15) In addition, the histone lysine methyltransferase SETD2-dependent H3K36 trimethylation is regarded to play an important role in homologous recombination repair and genome stability.(16) Dimethylation and trimethylation of H3K79 (H3K79me2 me3) are connected with the proximal transcribed area of active genes, and there are many similarities in between pattering of H3K4 methylation and that of H3K79 in mammalian chromatin.(17) As for histone arginine methylation, asymmetric dimethylation of H3R2 by PRMT6 counteracts the trimethylation of H3K4, which benefits in transcriptional repression.(18) Symmetric dimethylation of H3R8 by PRMT5 is linked to transcriptional repression and is tightly related with symmetric dimethylation of H4R3, that is also a transcriptional repression mark and generated by PRMT5.(19) Asymmetric dimethylation of both H3R17 and H3R26 is methylated by PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21338496 CARM1, viewed as as a transcriptional activation mark.(19) Interest-Other forms of protein modificationProteinprotein interactionProtein stability Non-histone methylation (Posttranslational modification)Subcellular localizationPromoter binding affinityProtein methyltransferasesProtein demethylasesHistone methylation (Epigenetics)Me Me Me MeFig. 1. Protein methyltransferases and demethylases principally regulate biological processes in two ways. A single is regulation of transcription for target downstream genes through methylation (Me) of histone proteins. The other is non-histone methylation as on the list of posttranslational modifications.Cancer Sci April 2016 vol. 107 no. four 2016 The Authors. Cancer Science published by John Wiley Sons Australia, Ltd on behalf of Japanese Cancer Association.www.wileyonlinelibrary.comjournalcasReview Hamamoto and Nakamuraingly, although symmetric dimethylation of H4R3 is actually a transcriptional repression mark, asymmetric dimethylation of H4R3 is often a transcriptional activation mark,(19) implying that symmetric dimethylation and asymmetric dimethylation are functionally different. Taken collectively, the aforementioned knowledge suggests that the position and modification status (the number of methyl group, or which isomer) defines the functions of histone methylation.Regulation of different pathways by way of non-histone methylation. The accumulated proof indicates that methylation ofnon-.