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Replisome stalling and stabilization at CGG repeats, which are responsible for chromosomal fragility.

ABSTRACT: Expanded CGG repeats cause chromosomal fragility and hereditary neurological disorders in humans. Replication forks stall at CGG repeats in a length-dependent manner in primate cells and in yeast. Saccharomyces cerevisiae proteins Tof1 and Mrc1 facilitate replication fork progression through CGG repeats. Remarkably, the fork-stabilizing role of Mrc1 does not involve its checkpoint function. Thus, chromosomal fragility might occur when forks stalled at expanded CGG repeats escape the S-phase checkpoint.

SUBMITTER: Voineagu I

PROVIDER: S-EPMC2837601 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Replisome stalling and stabilization at CGG repeats, which are responsible for chromosomal fragility.

Voineagu Irina I Surka Christine F CF Shishkin Alexander A AA Krasilnikova Maria M MM Mirkin Sergei M SM

Nature structural & molecular biology 20090111 2

Expanded CGG repeats cause chromosomal fragility and hereditary neurological disorders in humans. Replication forks stall at CGG repeats in a length-dependent manner in primate cells and in yeast. Saccharomyces cerevisiae proteins Tof1 and Mrc1 facilitate replication fork progression through CGG repeats. Remarkably, the fork-stabilizing role of Mrc1 does not involve its checkpoint function. Thus, chromosomal fragility might occur when forks stalled at expanded CGG repeats escape the S-phase chec ...[more]

PMID: 19136957

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