Shu Yinghua, Zhou Jialiang, Tang Wencheng, Lu Kai, Zhou Qiang, Zhang Guren
State Key Laboratory of Biological Control and Institute of Entomology, Sun Yat-sen University, Guangzhou 510275, China.
J Insect Physiol. 2009 Jul;55(7):608-16. doi: 10.1016/j.jinsphys.2009.03.005. Epub 2009 Mar 31.
Vitellogenin (Vg) cDNA from Spodoptera litura Fabricius was cloned and sequenced. The open reading frame (ORF) of Vg cDNA was 5247 nucleotides in length (GenBank Accession no. EU095334), which encoded for a protein of 1748 amino acids. S. litura Vg comprised three conserved regions (Vitellogenin-N domain, DUF1943 and von Willebrand factor type D domain (VWD)), a 17 amino-acid signal peptide and a RXXR cleavage signal (RTIR). The highly conserved GL/ICG motif, the DGXR motif and cysteine residues were found in the C-terminus of the Vg. Vg mRNA was found specifically in the female fat body. Vg expression was first transcribed in 6th day female pupae and levels increased with insect development. The maximum level of Vg mRNA appeared in 24-h-old adults. When S. litura larvae were exposed to lead (Pb) (25-200 mg Pb/kg), there was a significant inhibition in Vg of female adults. The start of Vg expression was advanced ahead by Pb, from 6th day pupae to 3rd day or 4th day pupae. Low levels of Vg in male adults were also induced by low concentrations of Pb (12.5 and 25 mg Pb/kg). These data show that Pb stress elicits an important Vg response in S. litura.
克隆并测序了斜纹夜蛾（Spodoptera litura Fabricius）的卵黄原蛋白（Vg）cDNA。Vg cDNA的开放阅读框（ORF）长度为5247个核苷酸（GenBank登录号：EU095334），编码一个由1748个氨基酸组成的蛋白质。斜纹夜蛾Vg包含三个保守区域（卵黄原蛋白-N结构域、DUF1943和血管性血友病因子D结构域（VWD））、一个17个氨基酸的信号肽和一个RXXR切割信号（RTIR）。在Vg的C末端发现了高度保守的GL/ICG基序、DGXR基序和半胱氨酸残基。Vg mRNA特异性地在雌虫脂肪体中发现。Vg表达首先在6日龄雌蛹中转录，且随着昆虫发育水平升高。Vg mRNA的最高水平出现在羽化24小时的成虫中。当斜纹夜蛾幼虫暴露于铅（Pb）（25 - 200 mg Pb/kg）时，雌虫成虫的Vg受到显著抑制。Pb使Vg表达的起始提前，从6日龄蛹提前到3日龄或4日龄蛹。低浓度的Pb（12.5和25 mg Pb/kg）也诱导雄虫成虫中出现低水平的Vg。这些数据表明，铅胁迫在斜纹夜蛾中引发了重要的Vg反应。
