title: The role of OsMSH5 in crossover formation during rice meiosis.
abstract: MSH5, a meiosis-specific member of the MutS-homolog family, is required for normal level of recombination in budding yeast, mice, Caenorhabditis elegans, and Arabidopsis. Here, we report the identification and characterization of its rice homolog, OsMSH5, and demonstrate its function in rice meiosis. Five independent Osmsh5 mutants exhibited normal vegetative growth and severe sterility. The synaptonemal complex is well installed in Osmsh5, while the chiasma frequency is greatly reduced to approximately 10% of that observed in the wild-type, leading to the homologous non-disjunction and complete sterile phenotype. OsMSH5 is predominantly expressed in panicles. Immunofluorescence studies indicate that OsMSH5 chromosomal localization is limited to the early meiotic prophase I. OsMSH5 can be loaded onto meiotic chromosomes in Oszip4, Osmer3, and hei10. However, those ZMM proteins cannot be localized normally in the absence of OsMSH5. Furthermore, the residual chiasmata were shown to be the least frequent among the zmm mutants, including Osmer3, Oszip4, hei10, and Osmsh5. Taken together, we propose that OsMSH5 functions upstream of OsZIP4, OsMER3, and HEI10 in class I crossover formation.
authors.affiliation: College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Luo
authors.forename: Ding
authors.initials: D
authors.lastname: Tang
authors.forename: Mo
authors.initials: M
authors.lastname: Wang
authors.forename: Weixiong
authors.initials: W
authors.lastname: Luo
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Baoxiang
authors.initials: B
authors.lastname: Qin
authors.forename: Yi
authors.initials: Y
authors.lastname: Shen
authors.forename: Kejian
authors.initials: K
authors.lastname: Wang
authors.forename: Yafei
authors.initials: Y
authors.lastname: Li
authors.forename: Zhukuan
authors.initials: Z
authors.lastname: Cheng
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D032461:Chromosomes, Plant / Q000235:genetics; D003001:Cloning, Molecular; D003434:Crossing Over, Genetic; D005455:Fluorescent Antibody Technique; D017343:Genes, Plant / Q000235:genetics; D008540:Meiosis / Q000235:genetics*; D049469:Meiotic Prophase I; D008677:Metaphase; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000166:cytology* / Q000235:genetics*; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013573:Synaptonemal Complex / Q000378:metabolism
chemical_list: D010940:Plant Proteins