TY - JOUR
T1 - Chitosan nanoparticles help double-stranded RNA escape from endosomes and improve RNA interference in the fall armyworm, Spodoptera frugiperda
AU - Gurusamy, Dhandapani
AU - Mogilicherla, Kanakachari
AU - Palli, Subba R.
N1 - Publisher Copyright:
© 2020 Wiley Periodicals, Inc.
PY - 2020/8/1
Y1 - 2020/8/1
N2 - 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 frugiperda by 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 of iap gene, growth retardation, and mortality. Processing of dsRNA into small interfering RNA was detected with chitosan-conjugated 32P-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.
AB - 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 frugiperda by 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 of iap gene, growth retardation, and mortality. Processing of dsRNA into small interfering RNA was detected with chitosan-conjugated 32P-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.
KW - RNA interference
KW - chitosan
KW - double-stranded RNA
KW - fall armyworm
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U2 - 10.1002/arch.21677
DO - 10.1002/arch.21677
M3 - Article
C2 - 32291818
AN - SCOPUS:85083442519
SN - 0739-4462
VL - 104
JO - Archives of Insect Biochemistry and Physiology
JF - Archives of Insect Biochemistry and Physiology
IS - 4
M1 - e21677
ER -