TY - JOUR
T1 - DNA Double-Strand Break Repair Pathway Choice Is Directed by Distinct MRE11 Nuclease Activities
AU - Shibata, Atsushi
AU - Moiani, Davide
AU - Arvai, Andrew S.
AU - Perry, Jefferson
AU - Harding, Shane M.
AU - Genois, Marie Michelle
AU - Maity, Ranjan
AU - van Rossum-Fikkert, Sari
AU - Kertokalio, Aryandi
AU - Romoli, Filippo
AU - Ismail, Amani
AU - Ismalaj, Ermal
AU - Petricci, Elena
AU - Neale, Matthew J.
AU - Bristow, Robert G.
AU - Masson, Jean Yves
AU - Wyman, Claire
AU - Jeggo, Penny A.
AU - Tainer, John A.
N1 - Funding Information:
We thank Drs. A. Carr, A. Oliver, K. Schlacher, and T. Paull for discussions; H. Ogiwara and M. Jasin for cell lines; and A. Rodrigue, Y. Coulombe, and C. Charbonnel for technical help. We thank the National Institutes of Health (CA117638 to J.A.T.), National Cancer Institute (P01 CA092584 to C.W. and J.A.T), and the Netherlands Organization for Scientific Research (VICI 700.56.441 to C.W.) for support. X-ray diffraction technologies at SIBYLS Beamline 12.3.1 at the Advanced Light Source are partly supported by the U.S. Department of Energy program Integrated Diffraction Analysis Technologies (IDAT). J.-Y.M. is a FRSQ Senior investigator and is supported by the CIHR. M.-M.G. is a CIHR Vanier scholar. P.A.J. is supported by the Medical Research Council, Association for International Cancer Research, Department of Health, and the Wellcome Trust.
PY - 2014/1/9
Y1 - 2014/1/9
N2 - MRE11 within the MRE11-RAD50-NBS1 (MRN) complex acts in DNA double-strand break repair (DSBR), detection, and signaling; yet, how its endo- and exonuclease activities regulate DSBR by nonhomologous end-joining (NHEJ) versus homologous recombination (HR) remains enigmatic. Here, we employed structure-based design with a focused chemical library to discover specific MRE11 endo- or exonuclease inhibitors. With these inhibitors, we examined repair pathway choice at DSBs generated in G2 following radiation exposure. While nuclease inhibition impairs radiation-induced replication protein A (RPA) chromatin binding, suggesting diminished resection, the inhibitors surprisingly direct different repair outcomes. Endonuclease inhibition promotes NHEJ in lieu of HR, while exonuclease inhibition confers a repair defect. Collectively, the results describe nuclease-specific MRE11 inhibitors, define distinct nuclease roles in DSB repair, and support a mechanism whereby MRE11 endonuclease initiates resection, thereby licensing HR followed by MRE11 exonuclease and EXO1/BLM bidirectional resection toward and away from the DNA end, which commits to HR.
AB - MRE11 within the MRE11-RAD50-NBS1 (MRN) complex acts in DNA double-strand break repair (DSBR), detection, and signaling; yet, how its endo- and exonuclease activities regulate DSBR by nonhomologous end-joining (NHEJ) versus homologous recombination (HR) remains enigmatic. Here, we employed structure-based design with a focused chemical library to discover specific MRE11 endo- or exonuclease inhibitors. With these inhibitors, we examined repair pathway choice at DSBs generated in G2 following radiation exposure. While nuclease inhibition impairs radiation-induced replication protein A (RPA) chromatin binding, suggesting diminished resection, the inhibitors surprisingly direct different repair outcomes. Endonuclease inhibition promotes NHEJ in lieu of HR, while exonuclease inhibition confers a repair defect. Collectively, the results describe nuclease-specific MRE11 inhibitors, define distinct nuclease roles in DSB repair, and support a mechanism whereby MRE11 endonuclease initiates resection, thereby licensing HR followed by MRE11 exonuclease and EXO1/BLM bidirectional resection toward and away from the DNA end, which commits to HR.
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U2 - 10.1016/j.molcel.2013.11.003
DO - 10.1016/j.molcel.2013.11.003
M3 - Article
C2 - 24316220
AN - SCOPUS:84892369333
SN - 1097-2765
VL - 53
SP - 7
EP - 18
JO - Molecular cell
JF - Molecular cell
IS - 1
ER -