The Biochemical Mechanism of Fork Regression in Prokaryotes and Eukaryotes-A Single Molecule Comparison.

ABSTRACT: The rescue of stalled DNA replication forks is essential for cell viability. Impeded but still intact forks can be rescued by atypical DNA helicases in a reaction known as fork regression. This reaction has been studied at the single-molecule level using the Escherichia coli DNA helicase RecG and, separately, using the eukaryotic SMARCAL1 enzyme. Both nanomachines possess the necessary activities to regress forks: they simultaneously couple DNA unwinding to duplex rewinding and the displacement of bound proteins. Furthermore, they can regress a fork into a Holliday junction structure, the central intermediate of many fork regression models. However, there are key differences between these two enzymes. RecG is monomeric and unidirectional, catalyzing an efficient and processive fork

SUBMITTER: Bianco PR 

PROVIDER: S-EPMC9368896 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature