刺五加ATP合酶β亚基基因的克隆与序列分析

目的]克隆刺五加叶绿体的ATP合酶β亚基cDNA并对其进行生物信息学分析。方法]根据已知物种叶绿体ATP合酶β亚基基因的序列,设计1对同源引物,通过RT-PCR扩增得到刺五加ATP合酶β亚基cDNA,并对其进行序列比对及结构预测分析。结果]RT-PCR扩增获得了长1099bp的刺五加ATP合酶β亚基cDNA,该基因编码366个氨基酸。序列比对及结构预测分析表明,刺五加ATP合酶β亚基基因编码的氨基酸与水稻的同源性最高,达96.41%。其二级结构中含有171个α螺旋（alpha helix）,占46.72%;53个延伸链（extended strand）,占14.48%;27个β折叠（beta turn）,占7.38%;115个无规则蜷曲（random coil）,占31.42%。第262～271位氨基酸为ATP合酶β亚基的标志性位点。整个多肽链无明显的疏水区域,初步认定为亲水性蛋白。结论]该试验克隆得到的ATP合酶β亚基基因为叶绿体ATP合酶β亚基基因,为研究刺五加能量代谢对植物次生代谢的影响及了解植物ATP合酶的结构与功能提供了必要的信息。

Cloning and Sequence Analysis of ATPase Beta Subunit Gene from Eleutherococcus senticosus

Objective] This study aimed to clone and analyze the cDNA of ATPase β subunit gene from Eleutherococcus senticosus.Method] A pair of homologous primers was designed according to the chloroplast ATPase β subunit gene sequences of the known species;then the gene cDNA of E.senticosus were amplified by RT-PCR and compared with that of the known species;its structure was predicted finally.Result] 1 099 bp of ATPase beta subunit cDNA of E.senticosus which encodes 366 amino acids was amplified by RT-PCR.Sequence comparison and structure prediction showed that amino acids encoded by the ATPase beta subunit gene of E.senticosus shared the highest homology,up to 96.41% with that of Oryza sativa.In the secondary structure,the protein contained 171 alpha helixes accounting for 46.72%,53 extended strands accounting for 14.48%,27 beta sheets accounting for 7.38% and 115 random coils which took up 31.42%.The amino acids 262-271 were the symbolic site of ATPase β subunit.The whole peptide chain had no obvious hydrophobic region and was primarily confirmed as a hydrophilic protein.Conclusion] The cNDA of ATPase β subunit gene cloned from E.senticosus in this study will provide reference for learning the effect of energy metabolism on secondary metabolism,structure and function of ATPase in E.senticosus.