TY - JOUR
T1 - Phosphorylation of EXO1 by CDKs 1 and 2 regulates DNA end resection and repair pathway choice
AU - Tomimatsu, Nozomi
AU - Mukherjee, Bipasha
AU - Catherine Hardebeck, Molly
AU - Ilcheva, Mariya
AU - Vanessa Camacho, Cristel
AU - Louise Harris, Janelle
AU - Porteus, Matthew
AU - Llorente, Bertrand
AU - Khanna, Kum K.um
AU - Burma, Sandeep
N1 - Funding Information:
S.B. is supported by grants from the National Institutes of Health (RO1 CA149461), National Aeronautics and Space Administration (NNX13AI13G), and the Cancer Prevention and Research Institute of Texas (RP100644). K.K.K. is supported by a National Health and Medical Research Council Senior Principal Research Fellowship. B.L. is supported by a grant from Foundation ARC. We are grateful to Professor David Chen for facilitating the laser micro-irradiation experiments. M.C.H. and M.I. completed this work in partial fulfillment of the requirements for their PhD degrees. M.C.H. is supported by a National Institute of General Medical Sciences training grant 5T32GM008203 in cellular and molecular biology.
PY - 2014
Y1 - 2014
N2 - Resection of DNA double-strand breaks (DSBs) is a pivotal step during which the choice between NHEJ and HR DNA repair pathways is made. Although CDKs are known to control initiation of resection, their role in regulating long-range resection remains elusive. Here we show that CDKs 1/2 phosphorylate the long-range resection nuclease EXO1 at four C-terminal S/TP sites during S/G2 phases of the cell cycle. Impairment of EXO1 phosphorylation attenuates resection, chromosomal integrity, cell survival and HR, but augments NHEJ upon DNA damage. In contrast, cells expressing phospho-mimic EXO1 are proficient in resection even after CDK inhibition and favour HR over NHEJ. Mutation of cyclin-binding sites on EXO1 attenuates CDK binding and EXO1 phosphorylation, causing a resection defect that can be rescued by phospho-mimic mutations. Mechanistically, phosphorylation of EXO1 augments its recruitment to DNA breaks possibly via interactions with BRCA1. In summary, phosphorylation of EXO1 by CDKs is a novel mechanism regulating repair pathway choice.
AB - Resection of DNA double-strand breaks (DSBs) is a pivotal step during which the choice between NHEJ and HR DNA repair pathways is made. Although CDKs are known to control initiation of resection, their role in regulating long-range resection remains elusive. Here we show that CDKs 1/2 phosphorylate the long-range resection nuclease EXO1 at four C-terminal S/TP sites during S/G2 phases of the cell cycle. Impairment of EXO1 phosphorylation attenuates resection, chromosomal integrity, cell survival and HR, but augments NHEJ upon DNA damage. In contrast, cells expressing phospho-mimic EXO1 are proficient in resection even after CDK inhibition and favour HR over NHEJ. Mutation of cyclin-binding sites on EXO1 attenuates CDK binding and EXO1 phosphorylation, causing a resection defect that can be rescued by phospho-mimic mutations. Mechanistically, phosphorylation of EXO1 augments its recruitment to DNA breaks possibly via interactions with BRCA1. In summary, phosphorylation of EXO1 by CDKs is a novel mechanism regulating repair pathway choice.
UR - https://www.scopus.com/pages/publications/84930948486
UR - https://www.scopus.com/pages/publications/84930948486#tab=citedBy
U2 - 10.1038/ncomms4561
DO - 10.1038/ncomms4561
M3 - Article
C2 - 24705021
AN - SCOPUS:84930948486
SN - 2041-1723
VL - 5
SP - 3561
JO - Nature communications
JF - Nature communications
M1 - 3561
ER -