Genetic interactions between the chromosome axis-associated protein Hop1 and homologous recombination determinants in Schizosaccharomyces pombe

• DOI: 10.1007/s00294-018-0827-7
• Publication Date: 2018-03-17T13:21:59Z
• Authors: Simon David Brown; Olga Dorota Jaros...; Alexander Lorenz
• Keywords: Hop1; Genes, Fungal; 610; homologous recombination; QH426 Genetics; chromosome axis; Evolution, Molecular; Recombinases; 03 medical and health sciences; Schizosaccharomyces; BB/F016964/1; meiosis; DNA Breaks, Double-Stranded; Amino Acid Sequence; Homologous Recombination; QH426; 0303 health sciences; Sequence Homology, Amino Acid; Synaptonemal Complex; DNA Helicases; Endonucleases; DNA-Binding Proteins; Meiosis; Schizosaccharomyces pombe; Biotechnology and Biological Sciences Research Council (BBSRC); Original Article; Schizosaccharomyces pombe Proteins; Chromosomes, Fungal; Protein Binding

AbstractHop1 is a component of the meiosis-specific chromosome axis and belongs to the evolutionarily conserved family of HORMA domain proteins. Hop1 and its orthologs in higher eukaryotes are a major factor in promoting double-strand DNA break formation and inter-homolog recombination. In budding yeast and mammals they are also involved in a meiotic checkpoint kinase cascade monitoring the completion of double-strand DNA break repair. We used the fission yeast,Schizosaccharomyces pombe, which lacks a canonical synaptonemal complex to test whether Hop1 has a role beyond supporting the generation of double-strand DNA breaks and facilitating inter-homolog recombination events. We determined how mutants of homologous recombination factors genetically interact withhop1, studied the role(s) of the HORMA domain of Hop1, and characterized a bio-informatically predicted interactor of Hop1, Aho1 (SPAC688.03c). Our observations indicate that in fission yeast, Hop1 does require its HORMA domain to support wild-type levels of meiotic recombination and localization to meiotic chromatin. Furthermore, we show thathop1Δonly weakly interacts genetically with mutants of homologous recombination factors, and in fission yeast likely has no major role beyond break formation and promoting inter-homolog events. We speculate that after the evolutionary loss of the synaptonemal complex, Hop1 likely has become less important for modulating recombination outcome during meiosis in fission yeast, and that this led to a concurrent rewiring of genetic pathways controlling meiotic recombination.