印度谷螟18S rDNA的克隆及定量PCR方法的建立

为挖掘储粮害虫印度谷螟的基因信息，开发用于生物系统进化研究的工具，建立基因表达水平的研究方法，本文利用分子生物学方法从印度谷螟幼虫体内克隆获得了18S rDNA 的基因全长序列（1888 bp，GenBank登录号为KJ836335）。利用邻位连接法（neighbor-joining）分别构建了基于18S rDNA 基因全长、保守序列II以及多变区的系统发育树，比较了与其他已知昆虫18S rDNA基因的同源性和遗传距离。与其它序列的系统发育树相比，其全长序列的系统发育树更能反映鳞翅目昆虫的亲缘关系，印度谷螟与大蜡螟的亲缘关系最近。此外，建立了以18S rDNA为内参基因的实时荧光定量PCR方法。

Cloning of the 18S rDNA and Establishment of Quantitative Real-time PCR for it from Plodia interpunctella

To mine the genomic information of stored-grain pests Plodia interpunctella, develop tools for evolutionary studies of biological systems and establish a method for quantitative gene expression studies, the full-length sequence of 18S rDNA gene (1888 bp, GenBank accession number: KJ836335)was obtained by cloning from the Plodia interpunctella larva using molecular biology method in this paper. The neighbor joining method was used to construct phylogenetic trees based on full-length sequence, conservative sequence II and the variable area of 18S rDNA gene respectively, comparing the homology and genetic distance with 18S rDNA gene of other known insects. The phylogenetic tree based on the full-length sequence can better reflect the genetic relationship of Lepidoptera insects compared with that based on the other sequences, Plodia interpunctella has the closest genetic relationship with the Galleria mellonella. In addition, the quantitative real-time PCR method was established with 18S rDNA as a reference gene.