Scully R, Chen J, Ochs RL, Keegan K, Hoekstra M, Feunteun J, Livingston DM. Dynamic changes of BRCA1 subnuclear location and phosphorylation state are initiated by DNA damage.
Cell 1997;
90:425-35. [PMID:
9267023 DOI:
10.1016/s0092-8674(00)80503-6]
[Citation(s) in RCA: 675] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BRCA1 localizes to discrete nuclear foci (dots) during S phase. Hydroxyurea-mediated DNA synthesis arrest of S phase MCF7 cells led to a loss of BRCA1 from these structures. Ultraviolet light, mitomycin C, or gamma irradiation produced a similar effect but with no concurrent arrest of DNA synthesis. BARD1 and Rad51, two proteins associated with the BRCA1 dots, behaved similarly. Loss of the BRCA1 foci was accompanied by a specific, dose-dependent change(s) in the state of BRCA1 phosphorylation. Three distinct DNA damaging agents preferentially induced this change in S phase. The S phase BRCA1 phosphorylation response to DNA damage occurred in cells lacking, respectively, two DNA damage-sensing protein kinases, DNA-PK and Atm, implying that neither plays a prime role in this process. Finally, after BRCA1 dot dispersal, BRCA1, BARD1, and Rad51 accumulated, focally, on PCNA+ replication structures, implying an interaction of BRCA1/BARD1/Rad51 containing complexes with damaged, replicating DNA. Taken together, the data imply that the BRCA1 S phase foci are dynamic physiological elements, responsive to DNA damage, and that BRCA1-containing multiprotein complexes participate in a replication checkpoint response.
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