Silencing of acetylcholinesterase gene of Helicoverpa armigera by siRNA affects larval growth and its life cycle

RNA interference is an effective means Of regulation of gene expression both in vitro and in vivo. We studied the effect of siRNA on larval development by selective targeting of the acetylcholinesterase (AChE) gene of Helicoverpa armigera. Chemically synthesized siRNA molecules were directly fed to H. armigera larvae along with the artificial diet. The siRNA treatment resulted in specific gene silencing of AChE and consequently brought about mortality, growth inhibition of larvae, reduction in the pupal weight, malformation and drastically reduced fecundity as compared to control larvae. Our studies suggest some novel roles for AChE in growth and development of insect larvae and demonstrate that siRNA can be readily taken up by insect larvae with their diet. (C) 2008 Elsevier Ltd. All rights reserved.