TY - JOUR
T1 - E3 ligase RFWD3 is a novel modulator of stalled fork stability in BRCA2-deficient cells
AU - Duan, Haohui
AU - Mansour, Sarah
AU - Reed, Rachel
AU - Gillis, Margaret K.
AU - Parent, Benjamin
AU - Liu, Ben
AU - Sztupinszki, Zsofia
AU - Birkbak, Nicolai
AU - Szallasi, Zoltan
AU - Elia, Andrew E.H.
AU - Garber, Judy E.
AU - Pathania, Shailja
N1 - Publisher Copyright:
© 2020 Duan et al. This article is distributed under the terms of an Attribution-Noncommercial-Share Alike-No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms/). After six months it is available under a Creative Commons License (Attribution-Noncommercial-Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/).
PY - 2020/6/1
Y1 - 2020/6/1
N2 - BRCA1/2 help maintain genomic integrity by stabilizing stalled forks. Here, we identify the E3 ligase RFWD3 as an essential modulator of stalled fork stability in BRCA2-deficient cells and show that codepletion of RFWD3 rescues fork degradation, collapse, and cell sensitivity upon replication stress. Stalled forks in BRCA2-deficient cells accumulate phosphorylated and ubiquitinated replication protein A (ubq-pRPA), the latter of which is mediated by RFWD3. Generation of this intermediate requires SMARCAL1, suggesting that it depends on stalled fork reversal. We show that in BRCA2-deficient cells, rescuing fork degradation might not be sufficient to ensure fork repair. Depleting MRE11 in BRCA2-deficient cells does block fork degradation, but it does not prevent fork collapse and cell sensitivity in the presence of replication stress. No such ubq-pRPA intermediate is formed in BRCA1-deficient cells, and our results suggest that BRCA1 may function upstream of BRCA2 in the stalled fork repair pathway. Collectively, our data uncover a novel mechanism by which RFWD3 destabilizes forks in BRCA2-deficient cells.
AB - BRCA1/2 help maintain genomic integrity by stabilizing stalled forks. Here, we identify the E3 ligase RFWD3 as an essential modulator of stalled fork stability in BRCA2-deficient cells and show that codepletion of RFWD3 rescues fork degradation, collapse, and cell sensitivity upon replication stress. Stalled forks in BRCA2-deficient cells accumulate phosphorylated and ubiquitinated replication protein A (ubq-pRPA), the latter of which is mediated by RFWD3. Generation of this intermediate requires SMARCAL1, suggesting that it depends on stalled fork reversal. We show that in BRCA2-deficient cells, rescuing fork degradation might not be sufficient to ensure fork repair. Depleting MRE11 in BRCA2-deficient cells does block fork degradation, but it does not prevent fork collapse and cell sensitivity in the presence of replication stress. No such ubq-pRPA intermediate is formed in BRCA1-deficient cells, and our results suggest that BRCA1 may function upstream of BRCA2 in the stalled fork repair pathway. Collectively, our data uncover a novel mechanism by which RFWD3 destabilizes forks in BRCA2-deficient cells.
UR - https://www.scopus.com/pages/publications/85084695045
UR - https://www.scopus.com/pages/publications/85084695045#tab=citedBy
U2 - 10.1083/JCB.201908192
DO - 10.1083/JCB.201908192
M3 - Article
C2 - 32391871
AN - SCOPUS:85084695045
SN - 0021-9525
VL - 219
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 6
M1 - 201908192
ER -