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Molecular mechanism of double Holliday junction dissolution.

ABSTRACT: Processing of homologous recombination intermediates is tightly coordinated to ensure that chromosomal integrity is maintained and tumorigenesis avoided. Decatenation of double Holliday junctions, for example, is catalysed by two enzymes that work in tight coordination and belong to the same 'dissolvasome' complex. Within the dissolvasome, the RecQ-like BLM helicase provides the translocase function for Holliday junction migration, while the topoisomerase III alpha-RMI1 subcomplex works as a proficient DNA decatenase, together resulting in double-Holliday-junction unlinking. Here, we review the available architectural and biochemical knowledge on the dissolvasome machinery, with a focus on the structural interplay between its components.

SUBMITTER: Swuec P

PROVIDER: S-EPMC4109787 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Molecular mechanism of double Holliday junction dissolution.

Swuec Paolo P Costa Alessandro A

Cell & bioscience 20140709

Processing of homologous recombination intermediates is tightly coordinated to ensure that chromosomal integrity is maintained and tumorigenesis avoided. Decatenation of double Holliday junctions, for example, is catalysed by two enzymes that work in tight coordination and belong to the same 'dissolvasome' complex. Within the dissolvasome, the RecQ-like BLM helicase provides the translocase function for Holliday junction migration, while the topoisomerase III alpha-RMI1 subcomplex works as a pro ...[more]

PMID: 25061510

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GEN1 promotes Holliday junction resolution by a coordinated nick and counter-nick mechanism.

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