对高芥酸品系M13、60Coy辐照得到的高芥酸油菜突变体H27和低芥酸品系742的FAD2基因克隆并测序.结果发现,FAD2基因存在两个拷贝FAD2.1(1155bp)、FAD2.2(1140bp).H27的FAD2.1与M13序列相同.但FAD2.2核苷酸序列中M13在409位点A(腺嘌呤)变成了T(鸟嘌呤),导致密码子由AGA变换为TGA(终止密码子),使H27中的FAD2.2基因的功能丧失,这可能是芥酸含量的提高原因.%In order to better understand the molecular mechanism of erucic acid mutation, the FAD2 genes of high erucic acid M13 strain, high-erucic acid rapeseed mutant H27 by 60Coγ irradiation and low erucic acid strain 742 were sequenced by our laboratory. The results showed that there were two copies of FAD2 gene FAD2. 1 ( 1155bp) , FAD2. 2 (1140bp) .Compared with the FAD2. 1 and FAD2. 2 gene sequences of H27 and M13 , both of them had the same FAD2. 1 nucleotide sequence and the different FAD2. 2 nucleotide sequence. The FAD2. 2 nucleotide sequence of M13 in the 409 point A ( adenine) was replaced by T ( guanine) in H27 , then the AGA codon transformed into TGA ( stop codon) , which resulted in FAD2. 2 gene some function loss. It might be the reason why H27 had higher erucic acid content than M13.
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