Female-specific expression of tTAV in immature Aedes aegypti

We have chosen enhancer and promoter DNA sequences from the hexamerin gene, Hex-1.2 of the rock pool mosquito Aedes atropalpus, to target ablation of the fat body in immature females of the dengue vector, Aedes aegypti.  Such destruction of an essential tissue in immature mosquitoes should provide a novel method for control of aedine mosquito populations.  Using components of the well-known “tet-off” system, fat body cell death will be induced by sex-specific expression of the tetracycline-responsive transcriptional activator (tTAV) and female-specific production of of the Drosophila melanogaster Head involution defective (Hid) protein to block inhibition of apoptosis exclusively in immature females.  We recently obtained of a set of transgenic lines carrying the Hex-1.2-tTAV fusion gene.  Using western blot analysis to detect the tTAV protein, we have characterized 10 transgenic lines and observed clear female-specific expression of tTAV in young pupae of 7 lines.  One line exhibited no detectable expression and one line showed high levels of expression in both sexes with only weak female bias.  Further examination of these tTAV transgenic lines at other developmental stages and production of effector lines, carrying the tetO-hidtransgene, are in progress. 

We gratefully acknowledge the support of NIH grant AI094168 and the Insect Transgenesis Facility of the University of Maryland.