FANCJ/BRIP1 recruitment and regulation of FANCD2 in DNA damage responses

Chromosoma. 2010 Dec;119(6):637-49. doi: 10.1007/s00412-010-0285-6. Epub 2010 Jul 31.

Abstract

FANCJ/BRIP1 encodes a helicase that has been implicated in the maintenance of genomic stability. Here, to better understand FANCJ function in DNA damage responses, we have examined the regulation of its cellular localization. FANCJ nuclear foci assemble spontaneously during S phase and are induced by various stresses. FANCJ foci colocalize with the replication fork following treatment with hydroxyurea, but not spontaneously. Using FANCJ mutants, we find that FANCJ helicase activity and the capacity to bind BRCA1 are both involved in FANCJ recruitment. Given similarities to the recruitment of another Fanconi anemia protein, FANCD2, we tested for colocalization of FANCJ and FANCD2. Importantly, these proteins show substantial colocalization, and FANCJ promotes the assembly of FANCD2 nuclear foci. This process is linked to the proper localization of FANCJ itself since both FANCJ and FANCD2 nuclear foci are compromised by FANCJ mutants that abrogate its helicase activity or interaction with BRCA1. Our results suggest that FANCJ is recruited in response to replication stress and that FANCJ/BRIP1 may serve to link FANCD2 to BRCA1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • BRCA1 Protein / genetics
  • BRCA1 Protein / metabolism
  • Cell Line
  • Cell Nucleus / genetics
  • Cell Nucleus / metabolism
  • DNA Damage*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Fanconi Anemia / genetics
  • Fanconi Anemia / metabolism*
  • Fanconi Anemia Complementation Group D2 Protein / genetics
  • Fanconi Anemia Complementation Group D2 Protein / metabolism*
  • Fanconi Anemia Complementation Group Proteins
  • Genomic Instability
  • Humans
  • Protein Binding
  • Protein Transport
  • RNA Helicases / genetics
  • RNA Helicases / metabolism*

Substances

  • BRCA1 Protein
  • DNA-Binding Proteins
  • Fanconi Anemia Complementation Group D2 Protein
  • Fanconi Anemia Complementation Group Proteins
  • BRIP1 protein, human
  • RNA Helicases