title: SHOC1, an XPF endonuclease-related protein, is essential for the formation of class I meiotic crossovers.
abstract: Crossovers (COs) are essential for the completion of meiosis in most species and lead to new allelic combinations in gametes. Two pathways of meiotic crossover formation have been distinguished. Class I COs, which are the major class of CO in budding yeast, mammals, Caenorhabditis elegans, and Arabidopsis, depend on a group of proteins called ZMM and rely on specific DNA structure intermediates that are processed to form COs. We identified a novel gene, SHOC1, involved in meiosis in Arabidopsis. Shoc1 mutants showed a striking reduction in the number of COs produced, a similar phenotype to the previously described Arabidopsis zmm mutants. The early steps of recombination, revealed by DMC1 foci, and completion of synapsis are not affected in shoc1 mutants. Double mutant analysis showed that SHOC1 acts in the same pathway as AtMSH5, a conserved member of the ZMM group. SHOC1 is thus a novel gene required for class I CO formation in Arabidopsis. Sequence similarity studies detected putative SHOC1 homologs in a large range of eukaryotes including human. SHOC1 appears to be related to the XPF endonuclease protein family, which suggests that it is directly involved in the maturation of DNA intermediates that lead to COs.
authors.affiliation: INRA, UR254, Station de Génétique et d'Amélioration des Plantes, F-78026 Versailles, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Macaisne
authors.forename: Maria
authors.initials: M
authors.lastname: Novatchkova
authors.forename: Lucie
authors.initials: L
authors.lastname: Peirera
authors.forename: Daniel
authors.initials: D
authors.lastname: Vezon
authors.forename: Sylvie
authors.initials: S
authors.lastname: Jolivet
authors.forename: Nicole
authors.initials: N
authors.lastname: Froger
authors.forename: Liudmila
authors.initials: L
authors.lastname: Chelysheva
authors.forename: Mathilde
authors.initials: M
authors.lastname: Grelon
authors.forename: Raphaël
authors.initials: R
authors.lastname: Mercier
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics*; D017173:Caenorhabditis elegans / Q000166:cytology / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000235:genetics*; D017124:Conserved Sequence; D003434:Crossing Over, Genetic; D018076:DNA, Complementary / Q000235:genetics; D005298:Fertility / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008322:Mammals; D008540:Meiosis; D008969:Molecular Sequence Data; D004718:Saccharomycetales / Q000166:cytology / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D029681:Arabidopsis Proteins; D029742:Caenorhabditis elegans Proteins; D018076:DNA, Complementary; D005656:Fungal Proteins