title: Fission yeast Swi5/Sfr1 and Rhp55/Rhp57 differentially regulate Rhp51-dependent recombination outcomes.
abstract: Several accessory proteins referred to as mediators are required for the full activity of the Rad51 (Rhp51 in fission yeast) recombinase. In this study, we analyzed in vivo functions of the recently discovered Swi5/Sfr1 complex from fission yeast. In normally growing cells, the Swi5-GFP protein localizes to the nucleus, where it forms a diffuse nuclear staining pattern with a few distinct foci. These spontaneous foci do not form in swi2Delta mutants. Upon UV irradiation, Swi5 focus formation is induced in swi2Delta mutants, a response that depends on Sfr1 function, and Sfr1 also forms foci that colocalize with damage-induced Rhp51 foci. The number of UV-induced Rhp51 foci is partially reduced in swi5Delta and rhp57Delta mutants and completely abolished in an swi5Delta rhp57Delta double mutant. An assay for products generated by HO endonuclease-induced DNA double-strand breaks (DSBs) reveals that Rhp51 and Rhp57, but not Swi5/Sfr1, are essential for crossover production. These results suggest that Swi5/Sfr1 functions as an Rhp51 mediator but processes DSBs in a manner different from that of the Rhp55/57 mediator.
authors.affiliation: International Graduate School of Arts and Sciences, Yokohama City University, Yokohama, Kanagawa, Japan.
authors.forename: Yufuko
authors.initials: Y
authors.lastname: Akamatsu
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tsutsui
authors.forename: Takashi
authors.initials: T
authors.lastname: Morishita
authors.forename: Md Shahjahan P
authors.initials: MS
authors.lastname: Siddique
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Kurokawa
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Ikeguchi
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Yamao
authors.forename: Benoit
authors.initials: B
authors.lastname: Arcangioli
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwasaki
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded / Q000528:radiation effects; D004249:DNA Damage; D004260:DNA Repair / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006570:Heterochromatin / Q000378:metabolism; D008856:Microscopy, Fluorescence; D011485:Protein Binding; D051135:Rad51 Recombinase / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D006570:Heterochromatin; C084232:RHP51 protein, S pombe; C121634:RHP55 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; C514357:Sfr1 protein, S pombe; C483769:Swi5 protein, S pombe; C465958:Swi6 protein, S pombe; D049452:Green Fluorescent Proteins; D051135:Rad51 Recombinase; D000251:Adenosine Triphosphatases; C442472:Rhp57 protein, S pombe