title: KAP-1 phosphorylation regulates CHD3 nucleosome remodeling during the DNA double-strand break response.
abstract: KAP-1 poses a substantial barrier to DNA double-strand break (DSB) repair within heterochromatin that is alleviated by ATM-dependent KAP-1 phosphorylation (pKAP-1). Here we address the mechanistic consequences of pKAP-1 that promote heterochromatic DSB repair and chromatin relaxation. KAP-1 function involves autoSUMOylation and recruitment of nucleosome deacetylation, methylation and remodeling activities. Although heterochromatin acetylation or methylation changes were not detected, radiation-induced pKAP-1 dispersed the nucleosome remodeler CHD3 from DSBs and triggered concomitant chromatin relaxation; pKAP-1 loss reversed these effects. Depletion or inactivation of CHD3, or ablation of its interaction with KAP-1(SUMO1), bypassed pKAP-1's role in repair. Though KAP-1 SUMOylation was unaffected after irradiation, CHD3 dissociated from KAP-1(SUMO1) in a pKAP-1-dependent manner. We demonstrate that KAP-1(Ser824) phosphorylation generates a motif that directly perturbs interactions between CHD3's SUMO-interacting motif and SUMO1, dispersing CHD3 from heterochromatin DSBs and enabling repair.
authors.affiliation: Genome Damage and Stability Centre, University of Sussex, East Sussex, UK. a.goodarzi@ucalgary.ca
authors.forename: Aaron A
authors.initials: AA
authors.lastname: Goodarzi
authors.forename: Thomas
authors.initials: T
authors.lastname: Kurka
authors.forename: Penelope A
authors.initials: PA
authors.lastname: Jeggo
mesh_terms: D000818:Animals; D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins / Q000502:physiology; D053903:DNA Breaks, Double-Stranded; D004265:DNA Helicases / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000502:physiology; D057809:HEK293 Cells; D006367:HeLa Cells; D006570:Heterochromatin / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D006801:Humans; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex; D051379:Mice; D009025:Morpholines / Q000494:pharmacology; D041681:NIH 3T3 Cells; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D009707:Nucleosomes / Q000187:drug effects / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D011753:Pyrones / Q000494:pharmacology; D012097:Repressor Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D025842:SUMO-1 Protein / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D058207:Sumoylation; D000076183:Tripartite Motif-Containing Protein 28; D025521:Tumor Suppressor Proteins / Q000502:physiology
chemical_list: C495818:2-morpholin-4-yl-6-thianthren-1-yl-pyran-4-one; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D006570:Heterochromatin; D006657:Histones; D009025:Morpholines; D009687:Nuclear Proteins; D009707:Nucleosomes; D011753:Pyrones; D012097:Repressor Proteins; D025842:SUMO-1 Protein; C495501:SUMO1 protein, human; D025521:Tumor Suppressor Proteins; C101116:TRIM28 protein, human; C103190:Trim28 protein, mouse; D000076183:Tripartite Motif-Containing Protein 28; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; C576325:Atm protein, mouse; D017346:Protein Serine-Threonine Kinases; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex; D004265:DNA Helicases; C115322:CHD3 protein, human