---

期 刊 ：植物保护学报 2010年

关键词：亚洲玉米螟；储存蛋白；基因克隆；序列分析；

Keywords:Ostrinia furnacalis, storage protein, gene cloning, sequence analysis,

摘 要 ：为研究亚洲玉米螟Ostrinia furnacalis (Guene)幼虫体内储存蛋白(SP)表达调控的分子机制,根据不同昆虫储存蛋白基因序列的保守区域,设计合成简并引物,采用RT-PCR技术从亚洲玉 米螟5龄幼虫中扩增出一段cDNA片段, 大小为892bp,编码297个氨基酸,预测分子量为35.7kD,理论等电点pI值为8.73。该基因序列中含有保守的幼虫储存蛋白(LSP)两个特征基序YFTEDIDLNTYYYYFHVDYP和TALRDPVFC。Blast P分析结果表明:该片段推导的氨基酸序列与斜纹夜蛾Spodoptera litura适量甲硫氨酸SP-1的一致性最高,为77%;与小菜蛾Plutella xylostella富含甲硫氨酸SP-1和SP-2、印度谷螟Plodia interpunctella SP、美国白蛾Hyphantria cunea SP-2和粉茎螟Sesamia nonagrioides适量甲硫氨酸SP氨基酸序列的一致性分别为74%、74%、72%、71%和65%。构建系统发育树分析了9种鳞翅目昆虫储存蛋白进化关系,结果显示:亚洲玉米螟cDNA片段氨基酸序列与小菜蛾富含甲硫氨酸SP-1的亲缘关系最近,与粉茎螟适量甲硫氨酸SP亲缘关系最远。

Abstract:In order to explore the molecular mechanism of expression and regulation of storage protein (SP) in larvae of Ostrinia furnacalis (Guene), the sequences of conserved regions of storage protein gene in different insects were used to design the degenerate primers, and a cDNA fragment with the size of 892bp encoding 297 amino acids was amplified from the 5th instar larvae by RT-PCR. The fragment was predicted with molecular weight of 35.7kD and pI value of 8.73. Two conserved larval storage protein (LSP) signature motifs, YFTEDIDLNTYYYYFHVDYP and TALRDPVFC, in the O.furnacalis SP (OfSP) gene were found. Blast P analysis showed that the amino acid sequence of O.furnacalis had the highest identity (77%) to that of Spodoptera litura moderately methionine-rich SP-1, and 74%, 74%, 72%, 71%, 65% to the Plutella xylostella methionine-rich SP-1 and SP-2, Plodia interpunctella SP, Hyphantria cunea SP-2, and Sesamia nonagrioides moderately methionine-rich SP, respectively. Phylogenetic analysis of SPs from nine lepidopterans showed that the genetic relationship between OfSP and P.xylostella methionine-rich SP-1 was the closest, while it was the farthest between OfSP and S.nonag- rioides moderately methionine-rich SP.

---