Crosstalk between CST and RPA regulates RAD51 activity during replication stress
Journal
Nature Communications
Journal Volume
12
Journal Issue
1
Pages
Article number 6412
Date Issued
2021
Author(s)
Abstract
Replication stress causes replication fork stalling, resulting in an accumulation of single-stranded DNA (ssDNA). Replication protein A (RPA) and CTC1-STN1-TEN1 (CST) complex bind ssDNA and are found at stalled forks, where they regulate RAD51 recruitment and foci formation in vivo. Here, we investigate crosstalk between RPA, CST, and RAD51. We show that CST and RPA localize in close proximity in cells. Although CST stably binds to ssDNA with a high affinity at low ionic strength, the interaction becomes more dynamic and enables facilitated dissociation at high ionic strength. CST can coexist with RPA on the same ssDNA and target RAD51 to RPA-coated ssDNA. Notably, whereas RPA-coated ssDNA inhibits RAD51 activity, RAD51 can assemble a functional filament and exhibit strand-exchange activity on CST-coated ssDNA at high ionic strength. Our findings provide mechanistic insights into how CST targets and tethers RAD51 to RPA-coated ssDNA in response to replication stress. ? 2021, The Author(s).
Subjects
bioaccumulation
cell
ionic composition
oxidative stress
protein
protein binding
Rad51 protein
replication factor A
Saccharomyces cerevisiae protein
DNA replication
gel mobility shift assay
genetics
HEK293 cell line
HeLa cell line
human
immunoprecipitation
metabolism
physiology
Saccharomyces cerevisiae
DNA Replication
Electrophoretic Mobility Shift Assay
HEK293 Cells
HeLa Cells
Humans
Immunoprecipitation
Protein Binding
Rad51 Recombinase
Replication Protein A
Saccharomyces cerevisiae Proteins
SDGs
Publisher
Nature Research
Type
journal article