An explanation for origin unwinding in eukaryotes.
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ABSTRACT:
SUBMITTER: Langston LD
PROVIDER: S-EPMC6634965 | biostudies-literature | 2019 Jul
REPOSITORIES: biostudies-literature
Publications
An explanation for origin unwinding in eukaryotes.
Langston Lance D LD O'Donnell Michael E ME
eLife 20190708
Twin CMG complexes are assembled head-to-head around duplex DNA at eukaryotic origins of replication. Mcm10 activates CMGs to form helicases that encircle single-strand (ss) DNA and initiate bidirectional forks. How the CMGs melt duplex DNA while encircling it is unknown. Here we show that <i>S. cerevisiae</i> CMG tracks with force while encircling double-stranded (ds) DNA and that in the presence of Mcm10 the CMG melts long blocks of dsDNA while it encircles dsDNA. We demonstrate that CMG track ...[more]
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