小麦胞质突变型雄性不育系85EA与其保持系线粒体DNA的比较研究

Comparative Analysis of Mitochondrial DNAs from a Mutated Cytoplasmic Male Sterile Line 85EA and Its Maintainer Line

85EA是通过电子束辐照获得的胞质突变型小麦不育系。采用RFL和RAPD技术对85EA及其保持系的线粒体DNA（mtDNA）进行了比较研究。RFL分析表明85EA线粒体基因组中coxⅡ基因的位置结构与保持系相比发生了变化；RAPD分析中引物OPD-15的扩增产物在不育系和保持系间存在明显差异，不育系的扩增产物比保持系多1条分子量为0．6kb的特异条带，用T-easyvector克隆该不育系特异条带并命名为OPD-150.6。以OPD-150.6为探针进行Southem杂交在不育系和保持系的mtDNA间检测到了多态性。实验检测到的不育系和保持系mtDNA间的多态性可能只是电子束辐照所引起的mtDNA结构变异的一部分。尽管目前对这种变异的确切机制尚不明确，但可以推测正是由于这些结构变异影响了线粒体基因组的正常功能，最终引起了雄性不育。

85EA is a mutated cytoplaswhc male sterile line of common wheat induced byelectron beam iedation. Comparahve analysis of mtDNAs from 85EA and itsmaintainer line was performed by using RFL and RAPD techniques. RFL analysisresults showed that the construction of coxⅡ gene in the mitochondrial genome of85EA was different from that in its maintalner line. A polymorphic amplified mtDNAfragment named OPD-15 0.6 which is specific to 85EA was obtained by RAPDtechnique and polymorphisms between mtDNAs of 85EA and its maintainer weredetected by Southem hybridization with the probe of OPD-150.6 . It is suggested thatthe CMS that of 85EA may be induced by the structure changes of mitochondrialgenome after electron beam irradiation, though the mechnism of mtDNA structurechange is not clear.