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The Fml1-MHF complex suppresses inter-fork strand annealing in fission yeast.

ABSTRACT: Previously we reported that a process called inter-fork strand annealing (IFSA) causes genomic deletions during the termination of DNA replication when an active replication fork converges on a collapsed fork (Morrow et al., 2017). We also identified the FANCM-related DNA helicase Fml1 as a potential suppressor of IFSA. Here, we confirm that Fml1 does indeed suppress IFSA, and show that this function depends on its catalytic activity and ability to interact with Mhf1-Mhf2 via its C-terminal domain. Finally, a plausible mechanism of IFSA suppression is demonstrated by the finding that Fml1 can catalyse regressed fork restoration in vitro.

SUBMITTER: Wong IN

PROVIDER: S-EPMC6952179 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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The Fml1-MHF complex suppresses inter-fork strand annealing in fission yeast.

Wong Io Nam IN Neo Jacqueline Ps JP Oehler Judith J Schafhauser Sophie S Osman Fekret F Carr Stephen B SB Whitby Matthew C MC

eLife 20191219

Previously we reported that a process called inter-fork strand annealing (IFSA) causes genomic deletions during the termination of DNA replication when an active replication fork converges on a collapsed fork (Morrow et al., 2017). We also identified the FANCM-related DNA helicase Fml1 as a potential suppressor of IFSA. Here, we confirm that Fml1 does indeed suppress IFSA, and show that this function depends on its catalytic activity and ability to interact with Mhf1-Mhf2 via its C-terminal doma ...[more]

PMID: 31855181

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