拟南芥雄性不育突变体ms1502的遗传及定位分析

通过EMS诱变、背景纯化与遗传分析，从拟南芥（Arabidopsis thaliana）中筛选到了一棵隐性单基因控制的雄性不育突变体ms1502。细胞学观察发现，突变体在小孢子从四分体释放出后花药绒毡层过早衰亡，小孢子的内容物不正常地凝聚，最终无法形成正常的花粉粒。利用图位克隆的方法对该基因MSl502进行了定位，结果表明MS1502位于第4条染色体上分子标记F25124和T12H20之间105kb区间内。目前该区间内尚未见到花药发育必需基因（不育基因）的报道，因此MS1502是一个控制花粉发育的新基因。

Genetic and Mapping Analysis of Arabidopsis thaliana Male Sterile Mutant ms1502 (Cruciferae)

Molecular and genetic characterizations of mutants have led to a better understanding of many developmental processes in the model system Arabidopsis thaliana.However,the anther and pollen development that is specific to plants has been little studied.A large-scale screening of mutants with male sterility was performed in this study to dissect genetically the anther and pollen development.An independent mutant line of male sterility controlled by a novel nuclear gene,designated MS1502,was generated and identified by ethyl-methae sulfonate (EMS) mutagenesis and genetic analysis.Genetics analysis indicated that the mutant was controlled by a single recessive gene MS1502.The phenotypic analysis indicated the MS1502 gene plays important role during anther and pollen development.Cytological analysis showed that anther tapetum of mutant degenerated earlier that of wild type after microspores were released from the tetrads,and that cytoplasm of microspores in mutant condensed abnormally,resulting in that mutant plant cannot produce viable pollens.With the further genetic analysis and the map-based cloning of gene MS1502,we have mapped it to a region of 105?kb between the molecular markers F25I24 and T12H20 on chromosome 4 using map-based cloning technique.