棉铃虫腺苷酸转移酶基因的克隆与分析

Cloning and analysis of adenine nucleotide translocase gene in Helicoverpa armigera

腺苷酸转移酶(ANT)是线粒体内膜上负责能量分子传导的转运蛋白,在细胞凋亡调控网络中有重要作用。本研究以棉铃虫幼虫组织的mRNA为模板,根据鳞翅目昆虫ant基因编码区保守序列设计引物,进行RT-PCR分析,同时结合5′、3′RACE方法扩增出棉铃虫ant基因的全长cDNA序列,cDNA全长为1190bp(GenBank登录号AY253868),具有完整的开放阅读框架(ORF,133～1033bp),编码蛋白为300个氨基酸,其中N端22个氨基酸为信号肽,引导ANT蛋白定位于线粒体内膜。该蛋白具有3个保守的线粒体穿膜功能结构域,形成能量分子传导的转运通道,催化细胞质中ADP和线粒体内ATP间进行跨膜交换。通过与其他昆虫的腺苷酸转移酶蛋白序列比较,发现该基因具有高度的保守性,氨基酸序列同源性都在90%左右。

A cDNA clone encoding the ADP/ATP translocase in Helicoverpa armigera has been identified by RT-PCR, 5＇ and 3＇RACE methods. Sequence analysis shows that it is 1 190 bp long and contains a single open reading frame （ORF, 133-1 033 bp） encoding a protein of 300 amino acids （GenBank submission number, AY253868）. The protein has a 22 aa signal peptide on its N-terminal, which leads the protein locating onto the inner membrane of the mitochondria. It also has three conserved domains of the mitochondrial carder protein forming a channel to exchange ATP and ADP energy molecule through the inner membrane of the mitochondria. It shows extensive similarities to the known ADP/ATP translocase polypeptides. The ADP/ATP translocase similarity was up to 90% in the Lepidoptera.