title: Regulation of p53 activity by its interaction with homeodomain-interacting protein kinase-2.
abstract: Transcriptional activity of p53, a central regulatory switch in a network controlling cell proliferation and apoptosis, is modulated by protein stability and post-translational modifications including phosphorylation and acetylation. Here we demonstrate that the human serine/threonine kinase homeodomain-interacting protein kinase-2 (HIPK2) colocalizes and interacts with p53 and CREB-binding protein (CBP) within promyelocytic leukaemia (PML) nuclear bodies. HIPK2 is activated by ultraviolet (UV) radiation and selectively phosphorylates p53 at Ser 46, thus facilitating the CBP-mediated acetylation of p53 at Lys 382, and promoting p53-dependent gene expression. Accordingly, the kinase function of HIPK2 mediates the increased expression of p53 target genes, which results in growth arrest and the enhancement of UV-induced apoptosis. Interference with HIPK2 expression by antisense oligonucleotides impairs UV-induced apoptosis. Our results imply that HIPK2 is a novel regulator of p53 effector functions involved in cell growth, proliferation and apoptosis.
authors.affiliation: Division of Immunochemistry (G0200) German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Hofmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Möller
authors.forename: Hüaeyin
authors.initials: H
authors.lastname: Sirma
authors.forename: Hanswalter
authors.initials: H
authors.lastname: Zentgraf
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Taya
authors.forename: Wulf
authors.initials: W
authors.lastname: Dröge
authors.forename: Hans
authors.initials: H
authors.lastname: Will
authors.forename: M Lienhard
authors.initials: ML
authors.lastname: Schmitz
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics* / Q000528:radiation effects; D050882:CREB-Binding Protein; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D002455:Cell Division / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D004789:Enzyme Activation / Q000528:radiation effects; D016147:Genes, Tumor Suppressor; D006801:Humans; D051379:Mice; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D016376:Oligonucleotides, Antisense; D000071156:Promyelocytic Leukemia Protein; D011485:Protein Binding; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D025521:Tumor Suppressor Proteins; D014466:Ultraviolet Rays
chemical_list: D002352:Carrier Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D016376:Oligonucleotides, Antisense; C513293:Pml protein, mouse; D000071156:Promyelocytic Leukemia Protein; D020033:Protein Isoforms; D015534:Trans-Activators; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; C070576:PML protein, human; D050882:CREB-Binding Protein; C494363:CREBBP protein, human; C494364:Crebbp protein, mouse; C115114:HIPK2 protein, human; C492003:Hipk2 protein, mouse; D017346:Protein Serine-Threonine Kinases