title: RanGAP is required for post-meiotic mitosis in female gametophyte development in Arabidopsis thaliana.
abstract: RanGAP is the GTPase-activating protein of the small GTPase Ran and is involved in nucleocytoplasmic transport in yeast and animals via the Ran cycle and in mitotic cell division. Arabidopsis thaliana has two copies of RanGAP, RanGAP1 and RanGAP2. To investigate the function of plant RanGAP, T-DNA insertional mutants were analysed. Arabidopsis plants with a null mutant of either RanGAP1 or RanGAP2 had no observable phenotype. Analysis of segregating progeny showed that double mutants in RanGAP1 and RanGAP2 are female gametophyte defective. Ovule clearing with differential interference contrast optics showed that mutant female gametophytes were arrested at interphase, predominantly after the first mitotic division following meiosis. In contrast, mutant pollen developed and functioned normally. These results show that the two RanGAPs are redundant and indispensable for female gametophyte development in Arabidopsis but dispensable for pollen development. Nuclear division arrest during a mitotic stage suggests a role for plant RanGAP in mitotic cell cycle progression during female gametophyte development.
authors.affiliation: Department of Plant Cellular and Molecular Biology, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Thushani
authors.initials: T
authors.lastname: Rodrigo-Peiris
authors.forename: Xianfeng Morgan
authors.initials: XM
authors.lastname: Xu
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zhao
authors.forename: Horng-Jing
authors.initials: HJ
authors.lastname: Wang
authors.forename: Iris
authors.initials: I
authors.lastname: Meier
mesh_terms: D000483:Alleles; D017360:Arabidopsis / Q000166:cytology* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D020090:Chromosome Segregation / Q000235:genetics; D003433:Crosses, Genetic; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D056130:Gametogenesis, Plant / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D055786:Gene Knockout Techniques; D005816:Genetic Complementation Test; D018745:Genome, Plant / Q000235:genetics; D005838:Genotype; D008540:Meiosis; D008938:Mitosis; D009154:Mutation / Q000235:genetics; D056771:Ovule / Q000166:cytology* / Q000235:genetics / Q000254:growth & development*; D053205:Pollen Tube / Q000235:genetics / Q000254:growth & development; D011401:Promoter Regions, Genetic / Q000235:genetics; D012639:Seeds / Q000235:genetics / Q000254:growth & development
chemical_list: C466201:AT3G63130 protein, Arabidopsis; D029681:Arabidopsis Proteins; D020690:GTPase-Activating Proteins