Prolonged gene knockdown in the tsetse fly Glossina by feeding double stranded RNA

• Published in: Insect molecular biology Vol. 18; no. 1; pp. 11 - 19
• Main Authors: Walshe, D.P, Lehane, S.M, Lehane, M.J, Haines, L.R
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.02.2009; Blackwell Publishing Ltd
• Subjects: Animals; Diptera; dsRNA feeding; Gene Expression Regulation - drug effects; Gene Knockdown Techniques - methods; Gene Silencing - drug effects; Glossina; Glossina morsitans morsitans; immunity; RNA, Double-Stranded - administration & dosage; RNA, Double-Stranded - pharmacology; RNAi; Trypanosoma; Trypanosoma - physiology; Tsetse Flies - drug effects; Tsetse Flies - genetics; Tsetse Flies - parasitology
• ISSN: 0962-1075; 1365-2583
• DOI: 10.1111/j.1365-2583.2008.00839.x

Reverse genetic studies based on RNA interference (RNAi) have revolutionized analysis of gene function in most insects. However the necessity of injecting double stranded RNA (dsRNA) inevitably compromises many investigations particularly those on immunity. Additionally, injection of tsetse flies often causes significant mortality. We demonstrate, at transcript and protein level, that delivering dsRNA in the bloodmeal to Glossina morsitans morsitans is as effective as injection in knockdown of the immunoresponsive midgut-expressed gene TsetseEP. However, feeding dsRNA fails to knockdown the fat body expressed transferrin gene, 2A192, previously shown to be silenced by dsRNA injection. Mortality rates of the dsRNA fed flies were significantly reduced compared to injected flies 14 days after treatment (Fed: 10.1%± 1.8%; injected: 37.9% ± 3.6% (Mean ± SEM)). This is the first demonstration in Diptera of gene knockdown by feeding and the first example of knockdown in a blood-sucking insect by including dsRNA in the bloodmeal.