棉铃虫载脂蛋白受体基因克隆及转录分析

载脂蛋白受体(lipophorin receptor, LpR)在昆虫体内脂质转运中发挥重要作用。为了明确棉铃虫载脂蛋白受体基因在其卵巢发育及饥饿胁迫中的功能, 本研究克隆了棉铃虫 HaLpR 基因的cDNA序列(GenBank登录号KU355886.1), 全长3 117 bp, 开放阅读框为2 643 bp, 编码880个氨基酸; 其氨基酸序列包含典型的低密度脂蛋白受体结构域, 与其他鳞翅目昆虫的LpR相似度>80%。荧光定量PCR检测结果显示, HaLpR 在雌蛾的卵巢和脂肪体组织中相对转录水平最高; 在雌蛾卵子发生期均有转录, 在雌蛾羽化后3 d表达量达到最高峰; 饥饿处理会抑制 HaLpR 在雌蛾卵巢和脂肪体中的转录。研究结果有助于解析HaLpR参与棉铃虫卵巢发育过程中的脂质转运以及应对饥饿胁迫的作用。

Molecular cloning and transcription analysis of lipoprotein receptor in Helicoverpa armigera (Lepidoptera: Noctuidae)

The lipophorin receptor (LpR) plays an important role in lipid transport in insects. To investigate the function of LpR in the ovary development and starvation stress in Helicoverpa armigera, the cDNA sequence of HaLpR was obtained using RT-PCR and RACE technology (GenBank accession no. KU355886.1). The length of cDNA was 3 117 bp including an open reading frame (ORF) of 2 643 bp, encoding 880 amino acids. It had the typical conserved domains of low-density lipoprotein (LDL) receptor family. Multiple sequence alignment revealed that HaLpR shared a high similarity (up to 80%) with other lepidopteran insects. qRT-PCR analysis showed that HaLpR was highly expressed in the ovary and fat body of female adult, and it was transcribed during oogenesis at a peak level in the 3-day-old female. Nevertheless, the expression of HaLpR in the ovary and fat body was suppressed after starvation. Our findings therefore help understand the roles of HaLpR in lipid transportation and starvation stress during ovarian development in H. armigera.