KAP-1 phosphorylation regulates CHD3 nucleosome remodeling during the DNA double-strand break response

Nat Struct Mol Biol. 2011 Jun 5;18(7):831-9. doi: 10.1038/nsmb.2077.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ataxia Telangiectasia Mutated Proteins
  • Cell Cycle Proteins / physiology
  • DNA Breaks, Double-Stranded*
  • DNA Helicases / chemistry
  • DNA Helicases / metabolism
  • DNA Helicases / physiology*
  • DNA Repair*
  • DNA-Binding Proteins / physiology
  • HEK293 Cells
  • HeLa Cells
  • Heterochromatin / metabolism
  • Histones / metabolism
  • Humans
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex
  • Mice
  • Morpholines / pharmacology
  • NIH 3T3 Cells
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / metabolism
  • Nuclear Proteins / physiology*
  • Nucleosomes / drug effects
  • Nucleosomes / metabolism*
  • Phosphorylation
  • Protein-Serine-Threonine Kinases / physiology
  • Pyrones / pharmacology
  • Repressor Proteins / chemistry
  • Repressor Proteins / metabolism
  • Repressor Proteins / physiology*
  • SUMO-1 Protein / chemistry
  • SUMO-1 Protein / metabolism
  • SUMO-1 Protein / physiology
  • Sumoylation
  • Tripartite Motif-Containing Protein 28
  • Tumor Suppressor Proteins / physiology

Substances

  • 2-morpholin-4-yl-6-thianthren-1-yl-pyran-4-one
  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • Heterochromatin
  • Histones
  • Morpholines
  • Nuclear Proteins
  • Nucleosomes
  • Pyrones
  • Repressor Proteins
  • SUMO-1 Protein
  • SUMO1 protein, human
  • Tumor Suppressor Proteins
  • TRIM28 protein, human
  • Trim28 protein, mouse
  • Tripartite Motif-Containing Protein 28
  • ATM protein, human
  • Ataxia Telangiectasia Mutated Proteins
  • Atm protein, mouse
  • Protein-Serine-Threonine Kinases
  • Mi-2 Nucleosome Remodeling and Deacetylase Complex
  • DNA Helicases
  • CHD3 protein, human