一例特异细胞质雄性不育小麦mtDNA特异片段的克隆和测序

CLONING AND SEQUENCING OF mtDNA SPECIAL FRAGMENTS OF A SPECIAL CMS IN WHEAT

以具有同质同核的二角型小麦花药外露不育系与花药不外露突变不育系为试材,对其mtDNA进行了RAPD分析,筛选出特异片段S32-1582、OPAA16-1753,并进行克隆与测序。结果表明:花药外露型不育系与花药不外露型不育系细胞质内mtDNA存在明显差异,而ctDNA之间不存在差异;二角型花药外露型不育系转化为花药不外露型不育系,很可能是由于mtDNA自发的重排引起的。其差异片段S32-1582、OPAA16-1753序列与核基因组上的序列具有同源性;供试线粒体基因组能够在较短的演化时间内发生变异,从而引起二角型花药外露型不育系向花药不外露型不育系的变异,其特异质核互作可能起重要作用。

The mitochondrial DNA（mtDNA） were analyzed between two male sterile lines,anther outside floret and anther inside floret with same Ae.bicornis cytoplasm in wheat by RAPD technique,and two specific bands S32-1582 and OPAA16-1753 were screened,then cloned and sequenced.The results showed that the difference was found between mitochondrial DNA（mtDNA） of two male sterile lines,but there was no difference in their chloroplast DNA（ctDNA）.Transfering the male sterile line of anther outside floret to anther inside floret line revealed that it was most likely due to the autonomic rearrangement of mtDNA.The sequences of S32-1582 and OPAA16-1753 were homologous with the nuclear genome sequence.The results indicated that the test plant mitochondrial genome mutated in a relatively short period of time,thus caused bicornis sterility with anther outside floret to anther inside floret,the specific nuclear-cytoplasmic interaction probably might play an important role in the process.