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  • Chitosan nanoparticles help double‐stranded RNA escape from endosomes and improve RNA interference in the fall armyworm, Spodoptera frugiperda
Title: Chitosan nanoparticles help double‐stranded RNA escape from endosomes and improve RNA interference in the fall armyworm, Spodoptera frugiperda
Abstract

RNA interference (RNAi) is a promising technology for the development of next‐generation insect pest control products. Though RNAi is efficient and systemic in coleopteran insects, it is inefficient and variable in lepidopteron insects. In this study, we explored the possibility of improving RNAi in the fall armyworm (FAW),Spodoptera frugiperdaby conjugating double‐stranded RNA (dsRNA) with biodegradable chitosan (Chi). dsRNA conjugated with chitosan was protected from degradation by endonucleases present in Sf9 cell‐conditioned medium, hemolymph, and midgut lumen contents collected from the FAW larvae. Chi–dsRNA complexes showed reduced accumulation in the endosomes of Sf9 cells and FAW tissues. Exposing chitosan formulated dsRNA in Sf9 cells and the tissues induced a significant knockdown of endogenous genes. Chi–dsIAP fed to FAW larvae induced knockdown ofiapgene, growth retardation, and mortality. Processing of dsRNA into small interfering RNA was detected with chitosan‐conjugated32P‐UTP‐labeled ds green fluorescent protein in Sf9 cells and FAW larval tissues. Overall, these data suggest that dsRNA conjugated with chitosan helps dsRNA escape from the endosomes and improves RNAi efficiency in FAW cells and tissues.

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Award ID(s):
1821936
NSF-PAR ID:
10144731
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Archives of Insect Biochemistry and Physiology
Volume:
104
Issue:
4
ISSN:
0739-4462
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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