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(Redirected from G9a-like protein)
Available structures
PDBOrtholog search: PDBe RCSB
AliasesEHMT1, EUHMTASE1, Eu-HMTase1, FP13812, GLP, GLP1, KMT1D, bA188C12.1, euchromatic histone lysine methyltransferase 1, EHMT1-IT1, KLEFS1
External IDsOMIM: 607001; MGI: 1924933; HomoloGene: 11698; GeneCards: EHMT1; OMA:EHMT1 - orthologs
RefSeq (mRNA)


RefSeq (protein)


Location (UCSC)Chr 9: 137.62 – 137.87 MbChr 2: 24.79 – 24.92 Mb
PubMed search[3][4]
View/Edit HumanView/Edit Mouse

Euchromatic histone-lysine N-methyltransferase 1, also known as G9a-like protein (GLP), is a protein that in humans is encoded by the EHMT1 gene.[5]


EHMT1 messenger RNA is alternatively spliced to produce three predicted protein isoforms. Starting from the N-terminus, the canonical isoform one has eight ankyrin repeats, a pre-SET, and a SET domains. Isoforms two and three have missing or incomplete C-terminal SET domains respectively.[6]


G9A-like protein (GLP) shares an evolutionary conserved SET domain with G9A, responsible for methyltransferase activity.[7] The SET domain primarily functions to establish and maintain H3K9 mono and di-methylation, a marker of faculative heterochromatin.[7][8] When transiently over expressed, G9A and GLP form homo- and heterodimers via their SET domain.[9] However, endogenously both enzymes function exclusively as a heteromeric complex.[9] Although G9A and GLP can exert their methyltransferase activities independently in vitro, if either G9a or Glp are knocked out in vivo, global levels of H3K9me2 are severely reduced and are equivalent to H3K9me2 levels in G9a and Glp double knockout mice.[7] Therefore, it is thought that G9A cannot compensate for the loss of GLP methyltransferase activity in vivo, and vice versa.[7] Another important functional domain, which G9A and GLP both share, is a region containing ankryin repeats, which is involved in protein-protein interactions. The ankyrin repeat domain also contains H3K9me1 and H3K9me2 binding sites.[7] Therefore, the G9A/GLP complex can both methylate histone tails and bind to mono- and di-methylated H3K9 to recruit molecules, such as DNA methyltransferases, to the chromatin.[10][7] H3K9me2 is a reversible modification and can be removed by a wide range of histone lysine demethylases (KDMs) including KDM1, KDM3, KDM4 and KDM7 family members.[7][11][12]

In addition to their role as histone lysine methyltransferases (HMTs), several studies have shown that G9A/GLP are also able to methylate a wide range of non-histone proteins.[13] However, as most of the reported methylation sites have been derived from mass spectrometry analyses, the function of many of these modifications remain unknown. Nevertheless, increasing evidence suggests methylation of non-histone proteins may influence protein stability, protein-protein interactions and regulate cellular signalling pathways.[14][13][15][16] For example, G9A/GLP can methylate a number of transcription factors to regulate their transcriptional activity, including MyoD,[17] C/EBP,[16] Reptin,[15] p53,[18] MEF2D,[19] MEF2C[20] and MTA1.[21] Furthermore, G9A/GLP are able to methylate non-histone proteins to regulate complexes which recruit DNA methyltransferases to gene promoters to repress transcription via the methylation of CpG islands.[22][23] Therefore, G9A and/or GLP have wide-ranging roles in development,[20][17] establishing and maintaining cell identity,[17][24] cell cycle regulation,[18] and cellular responses to environmental stimuli,[15]  which are dependent on their non-histone protein methyltransferase activity.

Clinical significance[edit]

Defects in this gene are a cause of chromosome 9q subtelomeric deletion syndrome (9q-syndrome or Kleefstra syndrome-1).[5]

Dysregulation of EHMT1 has been implicated in inflammatory and cardiovascular diseases.[25][26][27][28]


  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000181090Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000036893Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ a b "Entrez Gene: Euchromatic histone-lysine N-methyltransferase 1". Retrieved 2012-03-04.
  6. ^ Kleefstra T, Brunner HG, Amiel J, Oudakker AR, Nillesen WM, Magee A, et al. (August 2006). "Loss-of-function mutations in euchromatin histone methyl transferase 1 (EHMT1) cause the 9q34 subtelomeric deletion syndrome". American Journal of Human Genetics. 79 (2): 370–7. doi:10.1086/505693. PMC 1559478. PMID 16826528.
  7. ^ a b c d e f g Shinkai Y, Tachibana M (April 2011). "H3K9 methyltransferase G9a and the related molecule GLP". Genes & Development. 25 (8): 781–8. doi:10.1101/gad.2027411. PMC 3078703. PMID 21498567.
  8. ^ Xiong Y, Li F, Babault N, Dong A, Zeng H, Wu H, et al. (March 2017). "Discovery of Potent and Selective Inhibitors for G9a-Like Protein (GLP) Lysine Methyltransferase". Journal of Medicinal Chemistry. 60 (5): 1876–1891. doi:10.1021/acs.jmedchem.6b01645. PMC 5352984. PMID 28135087.
  9. ^ a b Tachibana M, Ueda J, Fukuda M, Takeda N, Ohta T, Iwanari H, et al. (April 2005). "Histone methyltransferases G9a and GLP form heteromeric complexes and are both crucial for methylation of euchromatin at H3-K9". Genes & Development. 19 (7): 815–26. doi:10.1101/gad.1284005. PMC 1074319. PMID 15774718.
  10. ^ Zhang T, Termanis A, Özkan B, Bao XX, Culley J, de Lima Alves F, et al. (April 2016). "G9a/GLP Complex Maintains Imprinted DNA Methylation in Embryonic Stem Cells". Cell Reports. 15 (1): 77–85. doi:10.1016/j.celrep.2016.03.007. PMC 4826439. PMID 27052169.
  11. ^ Delcuve GP, Rastegar M, Davie JR (May 2009). "Epigenetic control". Journal of Cellular Physiology. 219 (2): 243–50. doi:10.1002/jcp.21678. PMID 19127539. S2CID 39355478.
  12. ^ Cloos PA, Christensen J, Agger K, Helin K (May 2008). "Erasing the methyl mark: histone demethylases at the center of cellular differentiation and disease". Genes & Development. 22 (9): 1115–40. doi:10.1101/gad.1652908. PMC 2732404. PMID 18451103.
  13. ^ a b Biggar KK, Li SS (January 2015). "Non-histone protein methylation as a regulator of cellular signalling and function". Nature Reviews. Molecular Cell Biology. 16 (1): 5–17. doi:10.1038/nrm3915. PMID 25491103. S2CID 12558106.
  14. ^ Lee JY, Lee SH, Heo SH, Kim KS, Kim C, Kim DK, et al. (2015-10-22). "Novel Function of Lysine Methyltransferase G9a in the Regulation of Sox2 Protein Stability". PLOS ONE. 10 (10): e0141118. Bibcode:2015PLoSO..1041118L. doi:10.1371/journal.pone.0141118. PMC 4619656. PMID 26492085.
  15. ^ a b c Lee JS, Kim Y, Kim IS, Kim B, Choi HJ, Lee JM, et al. (July 2010). "Negative regulation of hypoxic responses via induced Reptin methylation". Molecular Cell. 39 (1): 71–85. doi:10.1016/j.molcel.2010.06.008. PMC 4651011. PMID 20603076.
  16. ^ a b Pless O, Kowenz-Leutz E, Knoblich M, Lausen J, Beyermann M, Walsh MJ, Leutz A (September 2008). "G9a-mediated lysine methylation alters the function of CCAAT/enhancer-binding protein-beta". The Journal of Biological Chemistry. 283 (39): 26357–63. doi:10.1074/jbc.M802132200. PMC 3258912. PMID 18647749.
  17. ^ a b c Ling BM, Bharathy N, Chung TK, Kok WK, Li S, Tan YH, et al. (January 2012). "Lysine methyltransferase G9a methylates the transcription factor MyoD and regulates skeletal muscle differentiation". Proceedings of the National Academy of Sciences of the United States of America. 109 (3): 841–6. Bibcode:2012PNAS..109..841L. doi:10.1073/pnas.1111628109. PMC 3271886. PMID 22215600.
  18. ^ a b Huang J, Dorsey J, Chuikov S, Pérez-Burgos L, Zhang X, Jenuwein T, et al. (March 2010). "G9a and Glp methylate lysine 373 in the tumor suppressor p53". The Journal of Biological Chemistry. 285 (13): 9636–41. doi:10.1074/jbc.M109.062588. PMC 2843213. PMID 20118233.
  19. ^ Choi J, Jang H, Kim H, Lee JH, Kim ST, Cho EJ, Youn HD (January 2014). "Modulation of lysine methylation in myocyte enhancer factor 2 during skeletal muscle cell differentiation". Nucleic Acids Research. 42 (1): 224–34. doi:10.1093/nar/gkt873. PMC 3874188. PMID 24078251.
  20. ^ a b Ow JR, Palanichamy Kala M, Rao VK, Choi MH, Bharathy N, Taneja R (September 2016). "G9a inhibits MEF2C activity to control sarcomere assembly". Scientific Reports. 6 (1): 34163. Bibcode:2016NatSR...634163O. doi:10.1038/srep34163. PMC 5036183. PMID 27667720.
  21. ^ Nair SS, Li DQ, Kumar R (February 2013). "A core chromatin remodeling factor instructs global chromatin signaling through multivalent reading of nucleosome codes". Molecular Cell. 49 (4): 704–18. doi:10.1016/j.molcel.2012.12.016. PMC 3582764. PMID 23352453.
  22. ^ Chang Y, Sun L, Kokura K, Horton JR, Fukuda M, Espejo A, et al. (November 2011). "MPP8 mediates the interactions between DNA methyltransferase Dnmt3a and H3K9 methyltransferase GLP/G9a". Nature Communications. 2: 533. Bibcode:2011NatCo...2..533C. doi:10.1038/ncomms1549. PMC 3286832. PMID 22086334.
  23. ^ Leung DC, Dong KB, Maksakova IA, Goyal P, Appanah R, Lee S, et al. (April 2011). "Lysine methyltransferase G9a is required for de novo DNA methylation and the establishment, but not the maintenance, of proviral silencing". Proceedings of the National Academy of Sciences of the United States of America. 108 (14): 5718–23. Bibcode:2011PNAS..108.5718L. doi:10.1073/pnas.1014660108. PMC 3078371. PMID 21427230.
  24. ^ Purcell DJ, Khalid O, Ou CY, Little GH, Frenkel B, Baniwal SK, Stallcup MR (July 2012). "Recruitment of coregulator G9a by Runx2 for selective enhancement or suppression of transcription". Journal of Cellular Biochemistry. 113 (7): 2406–14. doi:10.1002/jcb.24114. PMC 3350606. PMID 22389001.
  25. ^ Thienpont B, Aronsen JM, Robinson EL, Okkenhaug H, Loche E, Ferrini A, et al. (January 2017). "The H3K9 dimethyltransferases EHMT1/2 protect against pathological cardiac hypertrophy". The Journal of Clinical Investigation. 127 (1): 335–348. doi:10.1172/JCI88353. PMC 5199699. PMID 27893464.
  26. ^ Harman JL, Dobnikar L, Chappell J, Stokell BG, Dalby A, Foote K, et al. (November 2019). "Epigenetic Regulation of Vascular Smooth Muscle Cells by Histone H3 Lysine 9 Dimethylation Attenuates Target Gene-Induction by Inflammatory Signaling". Arteriosclerosis, Thrombosis, and Vascular Biology. 39 (11): 2289–2302. doi:10.1161/ATVBAHA.119.312765. PMC 6818986. PMID 31434493.
  27. ^ Levy D, Kuo AJ, Chang Y, Schaefer U, Kitson C, Cheung P, et al. (January 2011). "Lysine methylation of the NF-κB subunit RelA by SETD6 couples activity of the histone methyltransferase GLP at chromatin to tonic repression of NF-κB signaling". Nature Immunology. 12 (1): 29–36. doi:10.1038/ni.1968. PMC 3074206. PMID 21131967.
  28. ^ Harman JL, Jørgensen HF (October 2019). "The role of smooth muscle cells in plaque stability: Therapeutic targeting potential". British Journal of Pharmacology. 176 (19): 3741–3753. doi:10.1111/bph.14779. PMC 6780045. PMID 31254285.

External links[edit]

  • Overview of all the structural information available in the PDB for UniProt: Q9H9B1 (Histone-lysine N-methyltransferase EHMT1) at the PDBe-KB.