title: Srs2 promotes Mus81-Mms4-mediated resolution of recombination intermediates.
abstract: A variety of DNA lesions, secondary DNA structures or topological stress within the DNA template may lead to stalling of the replication fork. Recovery of such forks is essential for the maintenance of genomic stability. The structure-specific endonuclease Mus81-Mms4 has been implicated in processing DNA intermediates that arise from collapsed forks and homologous recombination. According to previous genetic studies, the Srs2 helicase may play a role in the repair of double-strand breaks and ssDNA gaps together with Mus81-Mms4. In this study, we show that the Srs2 and Mus81-Mms4 proteins physically interact in vitro and in vivo and we map the interaction domains within the Srs2 and Mus81 proteins. Further, we show that Srs2 plays a dual role in the stimulation of the Mus81-Mms4 nuclease activity on a variety of DNA substrates. First, Srs2 directly stimulates Mus81-Mms4 nuclease activity independent of its helicase activity. Second, Srs2 removes Rad51 from DNA to allow access of Mus81-Mms4 to cleave DNA. Concomitantly, Mus81-Mms4 inhibits the helicase activity of Srs2. Taken together, our data point to a coordinated role of Mus81-Mms4 and Srs2 in processing of recombination as well as replication intermediates.
authors.affiliation: Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic National Centre for Biomolecular Research, Masaryk University, Kamenice 5/A4, Brno 625 00, Czech Republic.
authors.forename: Melita
authors.initials: M
authors.lastname: Chavdarova
authors.affiliation: Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic.
authors.forename: Victoria
authors.initials: V
authors.lastname: Marini
authors.affiliation: Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital Brno, Brno, Czech Republic.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Sisakova
authors.affiliation: Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Sedlackova
authors.affiliation: Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark.
authors.forename: Dana
authors.initials: D
authors.lastname: Vigasova
authors.affiliation: Department of Genetics, Cancer Research Institute, Vlarska 7, 833 91 Bratislava, Slovakia.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Brill
authors.affiliation: Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Lisby
authors.affiliation: Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic National Centre for Biomolecular Research, Masaryk University, Kamenice 5/A4, Brno 625 00, Czech Republic International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital Brno, Brno, Czech Republic lkrejci@chemi.muni.cz.
authors.forename: Lumir
authors.initials: L
authors.lastname: Krejci
mesh_terms: D001483:Base Sequence; D004265:DNA Helicases / Q000502:physiology*; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000502:physiology*; D004720:Endonucleases / Q000502:physiology*; D045585:Flap Endonucleases / Q000502:physiology*; D008856:Microscopy, Fluorescence; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology*; D020798:Two-Hybrid System Techniques
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C061376:SRS2 protein, S cerevisiae; D004720:Endonucleases; D045585:Flap Endonucleases; C411624:MUS81 protein, S cerevisiae; C112337:MMS4 protein, S cerevisiae; D004265:DNA Helicases