穿心莲ent-柯巴基焦磷酸合酶基因的克隆与生物信息学分析

Cloning and Bioinformatic Analysis of a cDNA Encoding a Putative ent-Copalyl Diphosphate Synthase from Andrographis paniculata(Burm.f.) Nees

旨在克隆穿心莲CPS的编码基因,并进行序列分析。通过RT-PCR和cDNA末端快速扩增的技术从穿心莲叶片中获得目的基因;并利用生物信息学的方法对其编码蛋白进行功能分析。结果显示,获得了全长2 499 bp的cDNA序列,编码一个833 aa的蛋白。序列同源性比较表明,该蛋白与野甘草、咖啡等其他植物来源的CPS具有较高的同源性。保守功能结构域分析显示,该蛋白包含一个富含Asp残基的植物萜类合酶的共有保守功能域"DXDD",归属于萜类生物合成酶I类超级家族和顺式聚异戊二烯焦磷酸合酶超级家族。初步推测克隆得到了穿心莲CPS的编码基因(命名为ApCPS,GenBank登录号为JN216843.1)。

The aim of this study is to clone the cDNA encoding CPS from Andrographis paniculata（Burm.f.） Nees and analyze its function.RT-PCR combined with RACE-PCR was used to clone the CPS gene from the leaves of A.paniculta.Bioinformatic analysis was used to identify the gene.Results showed that a cDNA with the length of 2 499 bp encoding 833 amino acids was cloned.Homologous analysis showed that the deduced protein has extensive sequence similarities to CPS from other plants,such as Scoparia dulcis,Caffea arabica.The result of CD-search（Conserved Domain Database） indicated that the deduced protein contains a conserved Asp-rich motif ＂DXDD＂ of plant terpene synthases and belongs to isoprenoid biosynthsis Class I superfamily and trans-isoprenyl diphosphate synthases.A putative CPS gene from A.paniculata（designated as ApCPS,GenBank accession number JN216843） was successfully cloned.