title: AHP2 is required for bivalent formation and for segregation of homologous chromosomes in Arabidopsis meiosis.
abstract: A new Arabidopsis meiotic mutant has been isolated. Homozygous ahp2-1 (Arabidopsis homologue pairing 2) plants were sterile because of failure of both male and female gametophyte development. Fluorescent in situ hybridisation showed that in ahp2-1 male meiocytes, chromosomes did not form bivalents during prophase I and instead seemed to associate indiscriminately. Chromosome fragmentation, chromatin bridges and unbalanced segregation were seen in anaphase I and anaphase II. The ahp2-1 mutation was caused by a T-DNA insertion in an Arabidopsis homologue of meu13+, which has been implicated in homologous chromosome pairing during meiosis in Schizosaccharomyces pombe. Our results suggest that meu13+ function is conserved in higher eukaryotes and support the idea that Arabidopsis, yeast and mouse share a pairing pathway that is not present in Drosophila melanogaster and Caenorhabditis elegans.
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK.
authors.forename: Carla
authors.initials: C
authors.lastname: Schommer
authors.forename: Ali
authors.initials: A
authors.lastname: Beven
authors.forename: Tom
authors.initials: T
authors.lastname: Lawrenson
authors.forename: Peter
authors.initials: P
authors.lastname: Shaw
authors.forename: Robert
authors.initials: R
authors.lastname: Sablowski
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D020090:Chromosome Segregation / Q000235:genetics* / Q000502:physiology; D032461:Chromosomes, Plant / Q000235:genetics; D005298:Fertility / Q000235:genetics / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D008540:Meiosis / Q000235:genetics / Q000502:physiology; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010770:Phosphotransferases / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: C117967:AHP2 protein, Arabidopsis; D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; C433032:Meu13 protein, S pombe; D009687:Nuclear Proteins; D029702:Schizosaccharomyces pombe Proteins; D010770:Phosphotransferases