Delivery of gene‐specific dsRNA by microinjection and feeding induces RNAi response in Sri Lanka weevil, Myllocerus undecimpustulatus undatus Marshall

• Published in: Pest management science Vol. 76; no. 3; pp. 936 - 943
• Main Authors: Pinheiro, Daniele H, Taylor, Caitlin E, Wu, Ke, Siegfried, Blair D
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.03.2020; Wiley Subscription Services, Inc
• Subjects: Adenosine triphosphatase; Agronomy; Animals; Control methods; Double-stranded RNA; Feeding; Functional analysis; Gene expression; gene silencing; Genes; Glyceraldehyde-3-phosphate dehydrogenase; insect control; Insects; Microinjection; Microinjections; Organic chemistry; Pest control; Pests; reference gene; RNA Interference; RNA, Double-Stranded; RNA-mediated interference; Sri Lanka; Sri Lanka weevil; Stability analysis; Transcription; Weevils; Sri Lanka; gene silencing; reference gene; RNA interference; Sri Lanka weevil; insect control
• ISSN: 1526-498X; 1526-4998
• DOI: 10.1002/ps.5601

BACKGROUND RNA interference (RNAi) is widely used in entomological research for functional analysis of genes and is being considered as a new tool for insect pest management. Sri Lanka weevil (SLW) is a highly polyphagous pest of agronomically important plants, but currently only a few control methods are available for this insect. RESULTS In the present study, we evaluated the stability of candidate reference genes β‐ACT, α‐TUB, EF1‐α, RPL12 and GAPDH, and identified EF1‐α as the most reliable for gene expression normalization. Four target genes involved in different cellular processes, including Prosα2, RPS13, Snf7 and V‐ATPase A were selected to evaluate whether RNAi response in SLW adults can be triggered by microinjection and oral feeding of their double‐stranded RNAs (dsRNAs). Three days after injection of the dsRNAs for the target genes, their transcript levels were significantly reduced (up to 91.4%) when compared to the control. Additionally, weevils fed with the target dsRNAs showed significant decreases in gene transcript levels and significant mortality was observed in insects treated with Prosα2 and Snf7 dsRNAs (78.6 to 92.7%). CONCLUSION Our data demonstrate that microinjection and feeding of dsRNA produce a strong RNAi response in SLW, indicating that RNAi‐based strategies could be explored to develop a selective and environmentally safe control method against SLW. © 2019 Society of Chemical Industry Our study demonstrates that RNA interference (RNAi) response can be triggered in Sri Lanka weevil (SLW) by microinjection and feeding of double‐stranded RNA (dsRNA) indicating that RNAi‐based technologies could be a promising strategy for controlling this insect pest.