G9a and Glp methylate lysine 373 in the tumor suppressor p53.
The tumor suppressor p53 is regulated by numerous post-translational modifications. Lysine methylation has recently emerged as a key post-translational modification that alters the activity of p53. Here, we describe a novel lysine methylation site in p53 that is carried out by two homologous histone methyltransferases, G9a and Glp. G9a and Glp specifically methylate p53 at Lys(373), resulting mainly in dimethylation. During DNA damage, the overall level of p53 modified at Lys(373)me2 does not increase, despite the dramatic increase in total p53, indicating that Lys(373)me2 correlates with inactive p53. Further, reduction of G9a and/or Glp levels leads to a larger population of apoptotic cells. Examination of the Oncomine data base shows that G9a and Glp are overexpressed in various cancers compared with corresponding normal tissues, suggesting that they are putative oncogenes. These data reveal a new methylation site within p53 mediated by the methylases G9a and Glp and indicate that G9a is a potential inhibitory target for cancer treatment.
Huang
Jing
J
Laboratory of Cancer Biology and Genetics, NCI, National Institutes of Health, Bethesda, Maryland 20892; Wistar Institute, Philadelphia, Pennsylvania 19104. Electronic address: huangj3@mail.nih.gov.
Dorsey
Jean
J
Wistar Institute, Philadelphia, Pennsylvania 19104.
Chuikov
Sergei
S
New York University School of Medicine-Smilow Research Center, New York, New York 10016.
Zhang
Xinyue
X
Laboratory of Cancer Biology and Genetics, NCI, National Institutes of Health, Bethesda, Maryland 20892.
Jenuwein
Thomas
T
Research Institute of Molecular Pathology, Vienna A-1030, Austria; Max Planck Institute of Immunobiology, Freiburg im Breisgau 0761 5108-0, Germany.
Reinberg
Danny
D
New York University School of Medicine-Smilow Research Center, New York, New York 10016; University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey 08854.
Berger
Shelley L
SL
Wistar Institute, Philadelphia, Pennsylvania 19104; Departments of Cell and Developmental Biology, Biology, and Genetics, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
D001324:Autoantigens; D004249:DNA Damage; D019175:DNA Methylation; D005786:Gene Expression Regulation; D000077614:Golgi Matrix Proteins; D006649:Histocompatibility Antigens / Q000235:genetics / Q000502:physiology*; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D008239:Lysine / Q000737:chemistry*; D008745:Methylation; D009369:Neoplasms / Q000378:metabolism; D010455:Peptides / Q000737:chemistry; D011499:Protein Processing, Post-Translational; D011506:Proteins / Q000235:genetics / Q000502:physiology*; D034741:RNA, Small Interfering / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry* / Q000502:physiology*
D001324:Autoantigens; C427473:GOLGA6A protein, human; D000077614:Golgi Matrix Proteins; D006649:Histocompatibility Antigens; D010455:Peptides; D011506:Proteins; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D016159:Tumor Suppressor Protein p53; D000076983:Histone Methyltransferases; C445405:EHMT2 protein, human; D011495:Histone-Lysine N-Methyltransferase; D008239:Lysine