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SSB and the RecG DNA helicase: an intimate association to rescue a stalled replication fork.

ABSTRACT: In E. coli, the regression of stalled DNA replication forks is catalyzed by the DNA helicase RecG. One means of gaining access to the fork is by binding to the single strand binding protein or SSB. This interaction occurs via the wedge domain of RecG and the intrinsically disordered linker (IDL) of SSB, in a manner similar to that of SH3 domains binding to PXXP motif-containing ligands in eukaryotic cells. During loading, SSB remodels the wedge domain so that the helicase domains bind to the parental, duplex DNA, permitting the helicase to translocate using thermal energy. This translocation may be used to clear the fork of obstacles, prior to the initiation of fork regression.

SUBMITTER: Bianco PR

PROVIDER: S-EPMC5368079 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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SSB and the RecG DNA helicase: an intimate association to rescue a stalled replication fork.

Bianco Piero R PR Lyubchenko Yuri L YL

Protein science : a publication of the Protein Society 20170317 4

In E. coli, the regression of stalled DNA replication forks is catalyzed by the DNA helicase RecG. One means of gaining access to the fork is by binding to the single strand binding protein or SSB. This interaction occurs via the wedge domain of RecG and the intrinsically disordered linker (IDL) of SSB, in a manner similar to that of SH3 domains binding to PXXP motif-containing ligands in eukaryotic cells. During loading, SSB remodels the wedge domain so that the helicase domains bind to the par ...[more]

PMID: 28078722

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