Wang H M, Ketela T, Keller W A, Gleddie S C, Brown G G
Department of Biology, McGill University, Montreal, Quebec, Canada.
Plant Mol Biol. 1995 Feb;27(4):801-7. doi: 10.1007/BF00020232.
To identify regions of the mitochondrial genome from the polima or pol male-sterile cytoplasm of Brassica napus that are genetically correlated with cytoplasmic male sterility (CMS) we analyzed mtDNAs of three male-sterile somatic hybrids formed by the fusion of broccoli (B. oleracea L. var. italica) and pol CMS B. napus protoplasts. Fragments characteristic of a 4.5 kb DNA segment that comprises the single organizational difference between sterile pol and fertile cam Brassica mitochondrial genomes were found in all three sterile somatic hybrids. One of these hybrids possessed a mitochondrial genome that was, apart from a limited region around this 4.5 kb CMS-associated segment, collinear with B. oleracea mtDNA. Previous studies have indicated that expression of transcripts spanning the atp6 gene and a chimeric gene, orf24, located on this 4.5 kb DNA segment, is associated with male sterility. The present results indicate that the orf224/atp6 gene region is genetically correlated with male sterility and provide significant additional support for the view that this gene region may be involved in specifying the CMS trait.
为了鉴定甘蓝型油菜波利马或波里雄性不育细胞质中线粒体基因组与细胞质雄性不育（CMS）在遗传上相关的区域，我们分析了由西兰花（B. oleracea L. var. italica）与波利马CMS甘蓝型油菜原生质体融合形成的三个雄性不育体细胞杂种的线粒体DNA。在所有三个不育体细胞杂种中均发现了一个4.5 kb DNA片段的特征性片段，该片段包含不育的波利马和可育的卡姆甘蓝型油菜线粒体基因组之间唯一的组织差异。其中一个杂种拥有一个线粒体基因组，除了这个与4.5 kb CMS相关片段周围的有限区域外，与青花菜线粒体DNA共线。先前的研究表明，跨越该4.5 kb DNA片段上的atp6基因和一个嵌合基因orf24的转录本的表达与雄性不育有关。目前的结果表明，orf224/atp6基因区域与雄性不育在遗传上相关，并为该基因区域可能参与确定CMS性状的观点提供了重要的额外支持。
