TY - JOUR
T1 - BRCA1 participates in DNA decatenation
AU - Lou, Zhenkun
AU - Minter-Dykhouse, Katherine
AU - Chen, Junjie
N1 - Funding Information:
We thank R. Baer (Columbia University) for assisting us with the ubiquitination assay and J. Wood for providing suggestions and proofreading of this manuscript. This work is supported by grants from US National Institutes of Health (NIH RO1 CA89239 and CA92312 to J.C.). J.C. is a recipient of a Department of Defense (DOD) breast cancer career development award (DAMD17-02-1-0472). Z.L. is a recipient of a DOD breast cancer fellowship award (DAMD17-03-1-0610).
PY - 2005/7
Y1 - 2005/7
N2 - The tumor suppressor BRCA1 has an important function in the maintenance of genomic stability. Increasing evidence suggests that BRCA1 regulates cell cycle checkpoints and DNA repair after DNA damage. However, little is known about its normal function in the absence of DNA damage. Here we show that BRCA1 interacts and colocalizes with topoisomerase IIα in S phase cells. Similar to cells treated with the topoisomerase IIα inhibitor ICRF-193, BRCA1-deficient cells show lagging chromosomes, indicating a defect in DNA decatenation and chromosome segregation. More directly, BRCA1 deficiency results in defective DNA decatenation in vitro. Finally, topoisomerase IIα is ubiquitinated in a BRCA1-dependent manner, and topoisomerase IIα ubiquitination correlates with higher DNA decatenation activity. Together these results suggest an important role of BRCA1 in DNA decatenation and reveal a previously unknown function of BRCA1 in the maintenance of genomic stability.
AB - The tumor suppressor BRCA1 has an important function in the maintenance of genomic stability. Increasing evidence suggests that BRCA1 regulates cell cycle checkpoints and DNA repair after DNA damage. However, little is known about its normal function in the absence of DNA damage. Here we show that BRCA1 interacts and colocalizes with topoisomerase IIα in S phase cells. Similar to cells treated with the topoisomerase IIα inhibitor ICRF-193, BRCA1-deficient cells show lagging chromosomes, indicating a defect in DNA decatenation and chromosome segregation. More directly, BRCA1 deficiency results in defective DNA decatenation in vitro. Finally, topoisomerase IIα is ubiquitinated in a BRCA1-dependent manner, and topoisomerase IIα ubiquitination correlates with higher DNA decatenation activity. Together these results suggest an important role of BRCA1 in DNA decatenation and reveal a previously unknown function of BRCA1 in the maintenance of genomic stability.
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U2 - 10.1038/nsmb953
DO - 10.1038/nsmb953
M3 - Article
C2 - 15965487
AN - SCOPUS:22144450678
SN - 1545-9993
VL - 12
SP - 589
EP - 593
JO - Nature Structural and Molecular Biology
JF - Nature Structural and Molecular Biology
IS - 7
ER -