烟实夜蛾脂肪酸结合蛋白基因的克隆、序列分析与表达

Cloning,sequence analysis and expression of a fatty-acid binding protein gene of Helicoverpa assulta (Lepidoptera:Noctuidae)

应用RT-PCR技术,从烟实夜蛾Helicoverpa assulta幼虫脂肪体组织和血细胞总RNA中反转录扩增脂肪酸结合蛋白(fatty-acid binding protein,FABP)基因的cDNA片段,克隆到原核表达载体pGEX-4T-2上,转化大肠杆菌BL21(DE3),用IPTG进行诱导表达并进行检测。结果表明:扩增得到的片段全长399bp(GenBank登录号为DQ299942),编码132个氨基酸残基,预测分子量15.0kD,等点电5.83。FABP融合了GST。原核表达后经电泳检测到约41kD大小的外源蛋白,Western blot检测表明是目的蛋白。

A fatty-acid binding protein （FABP） gene of Helicoverpa assulta was cloned and expressed for further study on its function. The cDNA encoding the FABP was isolated from the fat body and blood cell of H. assulta larvae by reverse transcription polymerase chain reaction （RT-PCR）. The fragment containing FABP gene was inserted into pGEX-4T-2 expressive vector, and the expression was induced by IPTG and then checked. The results showed that FABP in H. assulta was 399 bp in length （registered in GenBank with the accession no. DQ299942）, encoding a peptide of 132 amino acid residues, and the predicted molecular weight was 15.0 kD. The FABP was fused with GST. Checked with SDS-PAGE, the prokaryotic expression product molecular weight was about 41 kD, and it was further confirmed with Western blot.