Polo-like kinase 1 (Plk1) regulates DNA replication origin firing and interacts with Rif1 in Xenopus.

ABSTRACT: The activation of eukaryotic DNA replication origins needs to be strictly controlled at multiple steps in order to faithfully duplicate the genome and to maintain its stability. How the checkpoint recovery and adaptation protein Polo-like kinase 1 (Plk1) regulates the firing of replication origins during non-challenged S phase remained an open question. Using DNA fiber analysis, we show that immunodepletion of Plk1 in the Xenopus in vitro system decreases replication fork density and initiation frequency. Numerical analyses suggest that Plk1 reduces the overall probability and synchrony of origin firing. We used quantitative chromatin proteomics and co-immunoprecipitations to demonstrate that Plk1 interacts with firing factors MTBP/Treslin/TopBP1 as well as with Rif1, a known regulator of

SUBMITTER: Ciardo D 

PROVIDER: S-EPMC8464078 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature