MRE11 complex links RECQ5 helicase to sites of DNA damage.

ABSTRACT: RECQ5 DNA helicase suppresses homologous recombination (HR) possibly through disruption of RAD51 filaments. Here, we show that RECQ5 is constitutively associated with the MRE11-RAD50-NBS1 (MRN) complex, a primary sensor of DNA double-strand breaks (DSBs) that promotes DSB repair and regulates DNA damage signaling via activation of the ATM kinase. Experiments with purified proteins indicated that RECQ5 interacts with the MRN complex through both MRE11 and NBS1. Functional assays revealed that RECQ5 specifically inhibited the 3'-->5' exonuclease activity of MRE11, while MRN had no effect on the helicase activity of RECQ5. At the cellular level, we observed that the MRN complex was required for the recruitment of RECQ5 to sites of DNA damage. Accumulation of RECQ5 at DSBs was neither dependen

SUBMITTER: Zheng L 

PROVIDER: S-EPMC2677886 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature