L A Avila
Auburn University, USA
Title: Delivery of lethal dsRNAs in insect diets by branched amphiphilic peptide capsules
Biography
Biography: L A Avila
Abstract
In this study we inhibited expression of two insect genes, BiP and Armet, through the
ingestion of dsRNA complexed with Branched Amphipathic Peptide Capsules (BAPCs). The dsRNA- BAPCs complexes were added to the diets of two insect species from two Orders: Acyrthosiphon pisum and Tribolium castaneum. The gene transcripts tested (BiP and Armet) are part of the unfolded protein response (UPR) and suppressing their translation resulted in lethality. For Acyrthosiphon pisum, ingestion of <10 ng of BiP-dsRNA associated with BAPCs led to the premature death of the aphids (t1/2 = 4 - 5 days) compared to ingestion of the same amounts of free BiP-dsRNA (t1/2 = 11-12 days). Tribolium castaneum was effectively killed by ingestion (by larvae only) using a combination of BiP-dsRNA and Armet-dsRNA complexed with BAPCs (75% of the subjects, n = 30) died as larvae or during eclosion (the emergence of adults from pupae). Feeding the two dsRNA alone resulted in fewer deaths (30% with n = 30). These results show that complexation of dsRNA with BAPCs greatly enhances the oral delivery of dsRNA over dsRNA alone in the diet. This approach provides a simpler method of delivering dsRNA compared to microinjection for studying in vivo protein function and for developing novel strategies for pest management.