TY - JOUR
T1 - Knockdown of the glutamate-gated chloride channel gene decreases emamectin benzoate susceptibility in the fall armyworm, Spodoptera frugiperda
AU - Wang, Xian Zheng
AU - Chen, Jia Sheng
AU - Wang, Wei
AU - Niu, Duo Bang
AU - Wu, Hui Zi
AU - Palli, Subba Reddy
AU - Cao, Hai Qun
AU - Sheng, Cheng Wang
N1 - Publisher Copyright:
© 2023 Elsevier Inc.
PY - 2023/11
Y1 - 2023/11
N2 - Emamectin benzoate (EB), a derivative of avermectin, is the primary insecticide used to control the fall armyworm (FAW) in China. However, the specific molecular targets of EB against FAW remain unclear. In this study, we cloned the glutamate-gated chloride channel (GluCl) gene, which is known to be a primary molecular target for avermectin. We first investigated the transcript levels of SfGluCl in FAW and found that the expression level of SfGluCl in the head and nerve cord was significantly higher than that in other tissues. Furthermore, we found that the expression level of SfGluCl was significantly higher in eggs than that in other developmental stages, including larvae, pupae, and adults. Additionally, we identified three variable splice forms of SfGluCl in exons 3 and 9 and found that their splice frequencies remained unaffected by treatment with the LC50 of EB. RNAi mediated knockdown of SfGluCl showed a significant reduction of 42% and 65% after 48 and 72 h of dsRNA feeding, respectively. Importantly, knockdown of SfGluCl sifgnificantly reduced LC50 and LC90 EB treatment induced mortality of FAW larvae by 15% and 44%, respectively, compared to the control group feeding by dsEGFP. In contrast, there were no significant changes in the mortality of FAW larvae treated with the control insecticides chlorantraniliprole and spinetoram. Finally, molecular docking simulations revealed that EB bound to the large amino-terminal extracellular domain of SfGluCl by forming five hydrogen bonds, two alkyl hydrophobic interactions and one salt bridge. These findings strongly suggest that GluCl may serve as one of the molecular targets of EB in FAW, shedding light on the mode of action of this important insecticide.
AB - Emamectin benzoate (EB), a derivative of avermectin, is the primary insecticide used to control the fall armyworm (FAW) in China. However, the specific molecular targets of EB against FAW remain unclear. In this study, we cloned the glutamate-gated chloride channel (GluCl) gene, which is known to be a primary molecular target for avermectin. We first investigated the transcript levels of SfGluCl in FAW and found that the expression level of SfGluCl in the head and nerve cord was significantly higher than that in other tissues. Furthermore, we found that the expression level of SfGluCl was significantly higher in eggs than that in other developmental stages, including larvae, pupae, and adults. Additionally, we identified three variable splice forms of SfGluCl in exons 3 and 9 and found that their splice frequencies remained unaffected by treatment with the LC50 of EB. RNAi mediated knockdown of SfGluCl showed a significant reduction of 42% and 65% after 48 and 72 h of dsRNA feeding, respectively. Importantly, knockdown of SfGluCl sifgnificantly reduced LC50 and LC90 EB treatment induced mortality of FAW larvae by 15% and 44%, respectively, compared to the control group feeding by dsEGFP. In contrast, there were no significant changes in the mortality of FAW larvae treated with the control insecticides chlorantraniliprole and spinetoram. Finally, molecular docking simulations revealed that EB bound to the large amino-terminal extracellular domain of SfGluCl by forming five hydrogen bonds, two alkyl hydrophobic interactions and one salt bridge. These findings strongly suggest that GluCl may serve as one of the molecular targets of EB in FAW, shedding light on the mode of action of this important insecticide.
KW - Alternative splicing
KW - Emamectin benzoate
KW - Glutamate-gated chloride channel
KW - Molecular docking
KW - RNA interference
KW - Spodoptera frugiperda
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U2 - 10.1016/j.pestbp.2023.105636
DO - 10.1016/j.pestbp.2023.105636
M3 - Article
C2 - 37945267
AN - SCOPUS:85173953379
SN - 0048-3575
VL - 196
JO - Pesticide Biochemistry and Physiology
JF - Pesticide Biochemistry and Physiology
M1 - 105636
ER -