A transferrin gene associated with development and 2-tridecanone tolerance in Helicoverpa armigera.

The full-length cDNA (2320 bp) encoding a putative iron-binding transferrin protein from Helicoverpa armigera was cloned and named HaTrf. The putative HaTrf sequence included 670 amino acids with a molecular mass of approximately 76 kDa. Quantitative PCR results demonstrated that the transcriptional level of HaTrf was significantly higher in the sixth instar and pupa stages as compared with other developmental stages. HaTrf transcripts were more abundant in fat bodies and in the epidermis than in malpighian tubules. Compared with the control, the expression of HaTrf increased dramatically 24 h after treatment with 2-tridecanone. Apparent growth inhibition with a dramatic body weight decrease was observed in larvae fed with HaTrf double-stranded RNA (dsRNA), as compared with those fed with green fluorescent protein dsRNA. RNA interference of HaTrf also significantly increased the susceptibility of larvae to 2-tridecanone. These results indicate the possible involvement of HaTrf in tolerance to plant secondary chemicals.

克隆了编码棉铃虫一种假定的铁结合转铁蛋白的全长cDNA（2320bp），并将其命名为HaTrf。推测的HaTrf序列包含670个氨基酸，分子量约为76kDa。定量PCR结果表明，与其他发育阶段相比，HaTrf的转录水平在六龄幼虫和蛹期显著更高。HaTrf转录本在脂肪体和表皮中比在马氏管中更为丰富。与对照相比，用2 - 十三烷酮处理24小时后，HaTrf的表达急剧增加。与喂食绿色荧光蛋白双链RNA（dsRNA）的幼虫相比，喂食HaTrf双链RNA的幼虫出现明显的生长抑制，体重显著下降。HaTrf的RNA干扰也显著增加了幼虫对2 - 十三烷酮的敏感性。这些结果表明HaTrf可能参与了对植物次生化学物质的耐受性。