title: A homolog of male sex-determining factor SRY cooperates with a transposon-derived CENP-B protein to control sex-specific directed recombination.
abstract: Schizosaccharomyces pombe cells switch mating type by replacing genetic information at the expressed mat1 locus with sequences copied from mat2-P or mat3-M silent donor loci. The choice of donor locus is dictated by cell type, such that mat2 is the preferred donor in M cells and mat3 is the preferred donor in P cells. Donor choice involves a recombination-promoting complex (RPC) containing Swi2 and Swi5. In P cells, the RPC localizes to a specific DNA element located adjacent to mat3, but in M cells it spreads across the silent mating-type region, including mat2-P. This differential distribution of the RPC regulates nonrandom choice of donors. However, cell-type-specific differences in RPC localization are not understood. Here we show that the mat1-M-encoded factor Mc, which shares structural and functional similarities with the male sex-determining factor SRY, is highly enriched at the swi2 and swi5 loci and promotes elevated levels of RPC components. Loss of Mc reduces Swi2 and Swi5 to levels comparable to those in P cells and disrupts RPC spreading across the mat2/3 region. Mc also localizes to loci expressed preferentially in M cells and to retrotransposon LTRs. We demonstrate that Mc localization at LTRs and at swi2 requires Abp1, a homolog of transposon-derived CENP-B protein and that loss of Abp1 impairs Swi2 protein expression and the donor choice mechanism. These results suggest that Mc modulates levels of recombination factors, which is important for mating-type donor selection and for the biased gene conversion observed during meiosis, where M cells serve as preferential donors of genetic information.
authors: Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors: Emiko
authors: E
authors: Matsuda
authors: Rie
authors: R
authors: Sugioka-Sugiyama
authors: Takeshi
authors: T
authors: Mizuguchi
authors: Sameet
authors: S
authors: Mehta
authors: Bowen
authors: B
authors: Cui
authors: Shiv I S
authors: SI
authors: Grewal
mesh_terms: D000483:Alleles; D047369:Chromatin Immunoprecipitation; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D002874:Chromosome Mapping; D004251:DNA Transposable Elements; D049770:Genes, Mating Type, Fungal; D006570:Heterochromatin / Q000378:metabolism; D008957:Models, Genetic; D011401:Promoter Regions, Genetic; D011995:Recombination, Genetic; D012568:Schizosaccharomyces / Q000235:genetics* / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D051876:Sex-Determining Region Y Protein / Q000378:metabolism*; D013696:Temperature
chemical_list: C555698:Cbh1 protein, S pombe; D002868:Chromosomal Proteins, Non-Histone; D004251:DNA Transposable Elements; D006570:Heterochromatin; D029702:Schizosaccharomyces pombe Proteins; D051876:Sex-Determining Region Y Protein; C574023:Swi2 protein, S pombe; C483769:Swi5 protein, S pombe