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Li Z, Wang Y, Qin Q, Chen L, Dang X, Ma Z, Zhou Z. Imidacloprid disrupts larval molting regulation and nutrient energy metabolism, causing developmental delay in honey bee Apis mellifera. eLife 2024; 12:RP88772. [PMID: 38466325 DOI: 10.7554/elife.88772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024] Open
Abstract
Imidacloprid is a global health threat that severely poisons the economically and ecologically important honeybee pollinator, Apis mellifera. However, its effects on developing bee larvae remain largely unexplored. Our pilot study showed that imidacloprid causes developmental delay in bee larvae, but the underlying toxicological mechanisms remain incompletely understood. In this study, we exposed bee larvae to imidacloprid at environmentally relevant concentrations of 0.7, 1.2, 3.1, and 377 ppb. There was a marked dose-dependent delay in larval development, characterized by reductions in body mass, width, and growth index. However, imidacloprid did not affect on larval survival and food consumption. The primary toxicological effects induced by elevated concentrations of imidacloprid (377 ppb) included inhibition of neural transmission gene expression, induction of oxidative stress, gut structural damage, and apoptosis, inhibition of developmental regulatory hormones and genes, suppression of gene expression levels involved in proteolysis, amino acid transport, protein synthesis, carbohydrate catabolism, oxidative phosphorylation, and glycolysis energy production. In addition, we found that the larvae may use antioxidant defenses and P450 detoxification mechanisms to mitigate the effects of imidacloprid. Ultimately, this study provides the first evidence that environmentally exposed imidacloprid can affect the growth and development of bee larvae by disrupting molting regulation and limiting the metabolism and utilization of dietary nutrients and energy. These findings have broader implications for studies assessing pesticide hazards in other juvenile animals.
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Affiliation(s)
- Zhi Li
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
| | - Yuedi Wang
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
| | - Qiqian Qin
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
| | - Lanchun Chen
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
| | - Xiaoqun Dang
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
| | - Zhengang Ma
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
| | - Zeyang Zhou
- College of Life Sciences, Chongqing Normal University, Chongqing, China
- Key Laboratory of Pollinator Resources Conservation and Utilization of the Upper Yangtze River, Ministry of Agriculture and Rural Affairs, Chongqing, China
- Chongqing Key Laboratory of Microsporidia Infection and Control, Chongqing, China
- The State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
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Corcoran JA, Mahaffee WF. Identification of a receptor for the sex pheromone of the vine mealybug, Planococcus ficus. Curr Res Insect Sci 2024; 5:100072. [PMID: 38314008 PMCID: PMC10837065 DOI: 10.1016/j.cris.2024.100072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 01/13/2024] [Accepted: 01/16/2024] [Indexed: 02/06/2024]
Abstract
The vine mealybug, Planococcus ficus, is a significant pest of vineyards in all major grape growing regions of the world. This pest causes significant aesthetic damage to berry clusters through its feeding behavior and secretion of "honeydew", which leads to significant decreases in crop marketability. More importantly, the vine mealybug is a vector of several grapevine viruses which are the causal agent of grapevine leafroll disease, one of the most destructive and economically devastating diseases of the grape industry worldwide. As there is no cure for grapevine leafroll disease, the only control measures available to reduce its spread are to remove infected vines whilst simultaneously controlling mealybug populations. Using transcriptomic libraries prepared from male and female mealybugs and a draft genome, we identified and evaluated expression levels of members of the odorant receptor gene family. Interestingly, of the 50 odorant receptors identified from these P. ficus genetic resources, only 23 were found to be expressed in females, suggesting this flightless life stage has a decreased reliance on the olfactory system. In contrast, 46 odorant receptors were found to be expressed in the alate male life stage. Heterologous expression of eight of these receptors, along with the obligate co-receptor, Orco, in HEK293 cells allowed for the identification of two receptors that respond to lavandulyl senecioate, the sole constituent of the sex pheromone used by this species. Interestingly, one of these receptors, PficOR8, also responded to the sex pheromone used by the Japanese mealybug, Planococcus kraunhiae. The data presented here represent the first report of odorant receptor gene family expression levels, as well as the identification of the first sex pheromone receptor, in soft-scale insects. The identification of a receptor for the vine mealybug sex pheromone will allow for the development of novel, species-specific pest control tools and monitoring devices.
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Affiliation(s)
- Jacob A Corcoran
- USDA - Agricultural Research Service, Biological Control of Insects Research Laboratory, Columbia, MO, USA
| | - Walter F Mahaffee
- USDA - Agricultural Research Service, Horticultural Crops Disease and Pest Management Research Unit, Corvallis, Oregon, USA
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Du Q, Shan Y, Hu H, Wu C, Wang D, Song X, Ma Y, Xi J, Ren X, Ma X, Ma Y. Fitness effect and transcription profile reveal sublethal effect of nitenpyram on the predator Chrysopa pallens (Neuroptera: Chrysopidae). Arch Insect Biochem Physiol 2024; 115:e22073. [PMID: 38288485 DOI: 10.1002/arch.22073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 11/14/2023] [Accepted: 12/01/2023] [Indexed: 02/01/2024]
Abstract
Although neonicotinoids are widely used and important insecticide, there are growing concerns about their effect on nontarget insects and other organisms. Moreover, the effects of nitenpyram (NIT), a second generation of neonicotinoid insecticides, on Chrysopa pallens are still unclear. Therefore, this study purposed to investigate the acute toxicity of NIT to C. pallens using the spotting method. To examine the potential effects of a sublethal dose of NIT (LD30 , 1.85 ng of active ingredient per insect) on C. pallens, we constructed the life tables and analyzed the transcriptome data. The life table results showed that the period of second instar larvae, adult pre-oviposition period and total pre-oviposition period were significantly prolonged after exposure to sublethal dose of NIT, but had no significant effects on the other instars, longevity, oviposition days, and fecundity. The population parameters, including the preadult survival rate, gross reproduction rate, net reproductive rate, the intrinsic rate of increase, and finite rate of increase, were not significantly affected, and only the mean generation time was significantly prolonged by NIT. Transcriptome analysis showed that there were 68 differentially expressed genes (DEGs), including 50 upregulated genes and 18 downregulated genes. Moreover, 13 DEGs related to heat shock protein, nose resistant to fluoxetine protein 6, and prophenoloxidas were upregulated. This study showed the potential effects of sublethal doses of NIT on C. pallens and provided a theoretical reference for the comprehensive application of chemical and biological control in integrated pest management.
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Affiliation(s)
- Qiankun Du
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Zhengzhou University, Zhengzhou, China
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Yongpan Shan
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Hongyan Hu
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Changcai Wu
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Dan Wang
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Xianpeng Song
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Yajie Ma
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Jianping Xi
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
| | - Xiangliang Ren
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Zhengzhou University, Zhengzhou, China
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
- Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji, China
| | - Xiaoyan Ma
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Zhengzhou University, Zhengzhou, China
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
- Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji, China
| | - Yan Ma
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Zhengzhou University, Zhengzhou, China
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China
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Carneiro LS, Santos CG, Resende MTCSD, Souza DLLD, Souza DDS, Souza AMDC, Motta JVDO, Nere PHA, Oliveira AHD, Serrão JE. Effects of the insecticide imidacloprid on the post-embryonic development of the honey bee Apis mellifera (Hymenoptera: Apidae). Sci Total Environ 2023; 905:167278. [PMID: 37741377 DOI: 10.1016/j.scitotenv.2023.167278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 09/15/2023] [Accepted: 09/20/2023] [Indexed: 09/25/2023]
Abstract
The widespread use of pesticides in agriculture has been linked to declines in bee populations worldwide. Imidacloprid is a widely used systemic insecticide that can be found in the pollen and nectar of plants and has the potential to negatively impact the development of bee larvae. We investigated the effects of oral exposure to a realistic field concentration (20.5 ng g-1) of imidacloprid on the midgut and fat body of Apis mellifera worker larvae. Our results showed that larvae exposed to imidacloprid exhibited changes in the midgut epithelium, including disorganization of the brush border, nuclear chromatin condensation, cytoplasm vacuolization, and release of cell fragments indication cell death. Additionally, histochemical analysis revealed that the midgut brush border glycocalyx was disorganized in exposed larvae. The fat body cells of imidacloprid-exposed larvae had a decrease in the size of lipid droplets from 50 to 8 μm and increase of 100 % of protein content, suggesting possible responses to the stress caused by the insecticide. However, the expression of de cdc20 gene, which plays a role in cell proliferation, was not affected in the midgut and fat body of treated larvae. These results suggest that imidacloprid negatively affects non-target organs during the larval development of A. mellifera potentially impacting this important pollinator species.
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Affiliation(s)
- Lenise Silva Carneiro
- Department of General Biology, Federal University of Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | | | | | | | - Diego Dos Santos Souza
- Department of Entomology, Federal University of Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | | | | | | | | | - José Eduardo Serrão
- Department of General Biology, Federal University of Viçosa, Viçosa, Minas Gerais 36570-900, Brazil.
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Lu Q, Xu S, Hao Z, Li Y, Huang Y, Ying S, Jing W, Zou S, Xu Y, Wang H. Dinotefuran exposure induces autophagy and apoptosis through oxidative stress in Bombyx mori. J Hazard Mater 2023; 458:131997. [PMID: 37423129 DOI: 10.1016/j.jhazmat.2023.131997] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 06/18/2023] [Accepted: 07/03/2023] [Indexed: 07/11/2023]
Abstract
As a third-generation neonicotinoid insecticide, dinotefuran is extensively used in agriculture, and its residue in the environment has potential effects on nontarget organisms. However, the toxic effects of dinotefuran exposure on nontarget organism remain largely unknown. This study explored the toxic effects of sublethal dose of dinotefuran on Bombyx mori. Dinotefuran upregulated reactive oxygen species (ROS) and malondialdehyde (MDA) levels in the midgut and fat body of B. mori. Transcriptional analysis revealed that the expression levels of many autophagy and apoptosis-associated genes were significantly altered after dinotefuran exposure, consistent with ultrastructural changes. Moreover, the expression levels of autophagy-related proteins (ATG8-PE and ATG6) and apoptosis-related proteins (BmDredd and BmICE) were increased, whereas the expression level of an autophagic key protein (sequestosome 1) was decreased in the dinotefuran-exposed group. These results indicate that dinotefuran exposure leads to oxidative stress, autophagy, and apoptosis in B. mori. In addition, its effect on the fat body was apparently greater than that on the midgut. In contrast, pretreatment with an autophagy inhibitor effectively downregulated the expression levels of ATG6 and BmDredd, but induced the expression of sequestosome 1, suggesting that dinotefuran-induced autophagy may promote apoptosis. This study reveals that ROS generation regulates the impact of dinotefuran on the crosstalk between autophagy and apoptosis, laying the foundation for studying cell death processes such as autophagy and apoptosis induced by pesticides. Furthermore, this study provides a comprehensive insight into the toxicity of dinotefuran on silkworm and contributes to the ecological risk assessment of dinotefuran in nontarget organisms.
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Affiliation(s)
- Qingyu Lu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shiliang Xu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhihua Hao
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yinghui Li
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuxin Huang
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shuye Ying
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wenhui Jing
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shiyu Zou
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yusong Xu
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Huabing Wang
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
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Pei H, He Z, Du R, Han C, Sheng Y, Wang J, Zhou X, Li W, Cao C, Sheng J, Wang X. Imidacloprid activates Kupffer cells pyroptosis to induce liver injury in mice via P2X7. Int Immunopharmacol 2023; 119:110179. [PMID: 37099941 DOI: 10.1016/j.intimp.2023.110179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/05/2023] [Accepted: 04/10/2023] [Indexed: 04/28/2023]
Abstract
AIM This work aimed to investigate the mechanism by which the environmental poison imidacloprid (IMI) induced liver injury. METHODS First of all, IMI at the ED50 = 100 μM was added to treat mouse liver Kupffer cells, thereafter, the occurrence of pyroptosis was detected by flow cytometry (FCM), transmission electron microscope (TEM), immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), RT-QPCT and Western-Blot (WB) assay. Furthermore, P2X7 expression was knocked out in Kupffer cells, and cells were treated with the P2X7 inhibitor, so as to observe the pyroptosis level induced by IMI after P2X7 suppression. In animal experiments, IMI was used to induce mouse liver injury, then the P2X7 inhibitor and pyroptosis inhibitor were added to treat the mice, respectively, so as to observe the effect on liver injury. RESULTS IMI induced Kupffer cell pyroptosis, P2X7 knockout or P2X7 inhibitor treatment suppressed the effect of IMI and reduced the pyroptosis level. In animal experiments, the application of both P2X7 inhibitor and pyroptosis inhibitor decreased the cell injury level. CONCLUSION IMI induces Kupffer cell pyroptosis via P2X7 and induce liver injury, and inhibiting the occurrence of pyroptosis can suppress the hepatotoxicity of IMI.
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Affiliation(s)
- Hongyan Pei
- College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun 130118, China
| | - Zhongmei He
- College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun 130118, China.
| | - Rui Du
- College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun 130118, China.
| | - Chenyang Han
- The Second Affiliated Hospital of Jiaxing University, 314001, China
| | - Yongjia Sheng
- The Second Affiliated Hospital of Jiaxing University, 314001, China
| | - Jin Wang
- The Second Affiliated Hospital of Jiaxing University, 314001, China
| | - Xiaohong Zhou
- The Second Affiliated Hospital of Jiaxing University, 314001, China
| | - Wenyan Li
- The Second Affiliated Hospital of Jiaxing University, 314001, China
| | - Chenxi Cao
- The Second Affiliated Hospital of Jiaxing University, 314001, China.
| | - Jian Sheng
- The Second Affiliated Hospital of Jiaxing University, 314001, China.
| | - Xiaoguang Wang
- The Second Affiliated Hospital of Jiaxing University, 314001, China.
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Nagloo N, Rigosi E, O'Carroll DC. Acute and chronic toxicity of imidacloprid in the pollinator fly, Eristalis tenax L., assessed using a novel oral bioassay. Ecotoxicol Environ Saf 2023; 251:114505. [PMID: 36646007 DOI: 10.1016/j.ecoenv.2023.114505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 11/09/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
Imidacloprid is a neonicotinoid neurotoxin that remains widely used worldwide and persists in the environment, resulting in chronic exposure to non-target insects. To accurately map dose-dependent effects of such exposure across taxa, toxicological assays need to assess relevant modes of exposure across indicator species. However, due to the difficulty of these experiments, contact bioassays are most frequently used to quantify dose. Here, we developed a novel naturalistic feeding bioassay to precisely measure imidacloprid ingestion and its toxicity for acute and chronic exposure in a dipteran, Eristalis tenax L., an important member of an under-represented pollinator group. Flies which ingested imidacloprid dosages lower than 12.1 ng/mg all showed consistent intake volumes and learned improved feeding efficiency over successive feeding sessions. In contrast, at doses of 12.1 ng/mg and higher flies showed a rapid onset of severe locomotive impairment which prevented them from completing the feeding task. Neither probability of survival nor severe locomotive impairment were significantly higher than the control group until doses of 1.43 ng/mg or higher were reached. We were unable to measure a median lethal dose for acute exposure (72 h) due to flies possessing a relatively high tolerance for imidacloprid. However, with chronic exposure (18 days), mortality went up and an LD50 of 0.41 ng/mg was estimated. Severe locomotive impairment (immobilisation) tended to occur earlier and at lower dosages than lethality, with ED50s of 7.82 ng/mg and 0.17 ng/mg for acute and chronic exposure, respectively. We conclude that adult Eristalis possess a much higher tolerance to this toxin than the honeybees that they mimic. The similarity of the LD50 to other dipterans such as the fruitfly and the housefly suggests that there may be a phylogenetic component to pesticide tolerance that merits further investigation. The absence of obvious adverse effects at sublethal dosages also underscores a need to develop better tools for quantifying animal behaviour to evaluate the impact of insecticides on foraging efficiency in economically important species.
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Affiliation(s)
| | - Elisa Rigosi
- Department of Biology Lund University, Lund, Sweden
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Qu X, Wang S, Lin G, Li M, Shen J, Wang D. The Synergistic Effect of Thiamethoxam and Synapsin dsRNA Targets Neurotransmission to Induce Mortality in Aphis gossypii. Int J Mol Sci 2022; 23:ijms23169388. [PMID: 36012653 PMCID: PMC9408958 DOI: 10.3390/ijms23169388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/20/2022] [Accepted: 08/17/2022] [Indexed: 11/16/2022] Open
Abstract
Sublethal doses of insecticides have many impacts on pest control and agroecosystems. Insects that survive a sublethal dose of insecticide could adapt their physiological and behavioral functions and resist this environmental stress, which contributes to the challenge of pest management. In this study, the sublethal effects of thiamethoxam on gene expression were measured through RNA sequencing in the melon aphid Aphis gossypii. Genes regulating energy production were downregulated, while genes related to neural function were upregulated. To further address the function of genes related to neurotransmission, RNA interference (RNAi) was implemented by transdermal delivery of dsRNA targeting synapsin (syn), a gene regulating presynaptic vesicle clustering. The gene expression of synapsin was knocked down and the mortality of aphids was increased significantly over the duration of the assay. Co-delivery of syn-dsRNA and thiamethoxam reversed the upregulation of synapsin caused by low-dose thiamethoxam and resulted in lethality to melon aphids, suggesting that the decreased presynaptic function may contribute to this synergistic lethal effect. In addition, the nanocarrier star polycation, which could bind both dsRNA and thiamethoxam, greatly improved the efficacy of lethality. These results increase our knowledge of the gene regulation induced by sublethal exposure to neonicotinoids and indicated that synapsin could be a potential RNAi target for resistance management of the melon aphid.
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