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Yeast Pif1 accelerates annealing of complementary DNA strands.

ABSTRACT: Pif1 is a helicase involved in the maintenance of nuclear and mitochondrial genomes in eukaryotes. Here we report a new activity of Saccharomyces cerevisiae Pif1, annealing of complementary DNA strands. We identified preferred substrates for annealing as those that generate a duplex product with a single-stranded overhang relative to a blunt end duplex. Importantly, we show that Pif1 can anneal DNA in the presence of ATP and Mg(2+). Pif1-mediated annealing also occurs in the presence of single-stranded DNA binding proteins. Additionally, we show that partial duplex substrates with 3'-single-stranded overhangs such as those generated during double-strand break repair can be annealed by Pif1.

SUBMITTER: Ramanagoudr-Bhojappa R

PROVIDER: S-EPMC4263423 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Yeast Pif1 accelerates annealing of complementary DNA strands.

Ramanagoudr-Bhojappa Ramanagouda R Byrd Alicia K AK Dahl Christopher C Raney Kevin D KD

Biochemistry 20141126 48

Pif1 is a helicase involved in the maintenance of nuclear and mitochondrial genomes in eukaryotes. Here we report a new activity of Saccharomyces cerevisiae Pif1, annealing of complementary DNA strands. We identified preferred substrates for annealing as those that generate a duplex product with a single-stranded overhang relative to a blunt end duplex. Importantly, we show that Pif1 can anneal DNA in the presence of ATP and Mg(2+). Pif1-mediated annealing also occurs in the presence of single-s ...[more]

PMID: 25393406

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