Pham D Q-D, Shaffer J J, Chavez C A, Douglass P L
Department of Biological Sciences, University of Wisconsin-Parkside, Kenosha, WI 53141-2000, USA.
Insect Biochem Mol Biol. 2003 Jan;33(1):51-62. doi: 10.1016/s0965-1748(02)00167-4.
Mosquitoes are responsible for the transmission of numerous human diseases. The recent development of transgenic mosquitoes provides a new tool to examine molecular interactions between insect vectors and the pathogens they transmit. One focus in generating transgenic mosquito lies on expressing anti-pathogenic proteins at primary sites of pathogenic invasions, specifically the mosquito gut. Promoters that direct the expression of anti-pathogenic proteins in the mosquito gut are thus sought after because they may provide ways to hinder pathogenic development in the mosquito. Here, we report the identification and mapping of a strong promoter from the Aedes aegypti ferritin heavy-chain homologue (HCH) gene. All known insect ferritin HCH genes are expressed in the gut and inducible by an iron overload. Our transfection assays and DNase I footprinting analyses show that the mosquito ferritin HCH-gene contains regulatory elements both upstream and downstream of the transcriptional start site. The promoter of this gene contains a CF2 site, two GATA-binding sites, an E2F site, a TATA-box, an AP-1 site and a C/EBP binding site.
蚊子是多种人类疾病的传播媒介。转基因蚊子的最新发展为研究昆虫载体与其传播的病原体之间的分子相互作用提供了一种新工具。培育转基因蚊子的一个重点是在病原体入侵的主要部位，特别是蚊子肠道中表达抗病原体蛋白。因此，人们一直在寻找能指导蚊子肠道中抗病原体蛋白表达的启动子，因为它们可能提供阻碍蚊子体内病原体发育的方法。在这里，我们报告了从埃及伊蚊铁蛋白重链同源物（HCH）基因中鉴定和定位一个强启动子。所有已知的昆虫铁蛋白HCH基因都在肠道中表达，并可由铁过载诱导。我们的转染实验和DNase I足迹分析表明，蚊子铁蛋白HCH基因在转录起始位点的上游和下游都含有调控元件。该基因的启动子包含一个CF2位点、两个GATA结合位点、一个E2F位点、一个TATA框、一个AP-1位点和一个C/EBP结合位点。
