Yi Zhang , Ya-Nan Liu , Yu-Dan Li , Tong-Xian Liu , Xing-Xing Wang
{"title":"上颌触须感受器介导舌蚜避尸。","authors":"Yi Zhang , Ya-Nan Liu , Yu-Dan Li , Tong-Xian Liu , Xing-Xing Wang","doi":"10.1016/j.jinsphys.2025.104886","DOIUrl":null,"url":null,"abstract":"<div><div>The ladybird <em>Harmonia axyridis</em> is an important predatory natural enemy with a broad dietary spectrum and few avoided food sources. Nevertheless, it shows avoidance behavior toward aphid corpses, likely to minimize the risk of pathogen infection in the wild. The molecular basis of this behavior remains unclear, and gustatory receptors (GRs) are hypothesized to be involved. Here, we examined the avoidance of <em>H. axyridis</em> toward pea aphid (<em>Acyrthosiphon pisum</em>) corpses and investigated the role of candidate <em>GR</em> genes in contact chemoreception via the maxillary palps. Using SEM and immunofluorescence, we characterized the microstructure of the maxillary palps and mapped neuronal distributions. Behavioral assays combined with RNAi were performed to evaluate three candidate <em>GR</em> genes associated with corpse recognition. Our results show that feeding behavior on <em>A. pisum</em> is largely determined by gustatory input through maxillary palp contact. The palp surface is densely covered with sensilla, and internally the tissue displays a complementary distribution of dopaminergic and serotonergic neurons. RNAi assays demonstrated that three <em>GR</em> genes (<em>GR2-like</em>, <em>GR28b-like</em>, and <em>GR64e-like</em>) mediate corpse avoidance. Silencing <em>GR2-like</em> alone significantly reduced avoidance, while simultaneous knockdown of <em>GR28b-like</em> and <em>GR64e-like</em> further weakened the response, suggesting functional interactions among gustatory receptors in <em>H. axyridis</em>. These findings reveal a gustatory mechanism underlying corpse avoidance in predatory insects and provide insights relevant to biological control and artificial diet development.</div></div>","PeriodicalId":16189,"journal":{"name":"Journal of insect physiology","volume":"166 ","pages":"Article 104886"},"PeriodicalIF":2.3000,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Maxillary palp gustatory receptors mediate aphid corpses avoidance in Harmonia axyridis\",\"authors\":\"Yi Zhang , Ya-Nan Liu , Yu-Dan Li , Tong-Xian Liu , Xing-Xing Wang\",\"doi\":\"10.1016/j.jinsphys.2025.104886\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The ladybird <em>Harmonia axyridis</em> is an important predatory natural enemy with a broad dietary spectrum and few avoided food sources. Nevertheless, it shows avoidance behavior toward aphid corpses, likely to minimize the risk of pathogen infection in the wild. The molecular basis of this behavior remains unclear, and gustatory receptors (GRs) are hypothesized to be involved. Here, we examined the avoidance of <em>H. axyridis</em> toward pea aphid (<em>Acyrthosiphon pisum</em>) corpses and investigated the role of candidate <em>GR</em> genes in contact chemoreception via the maxillary palps. Using SEM and immunofluorescence, we characterized the microstructure of the maxillary palps and mapped neuronal distributions. Behavioral assays combined with RNAi were performed to evaluate three candidate <em>GR</em> genes associated with corpse recognition. Our results show that feeding behavior on <em>A. pisum</em> is largely determined by gustatory input through maxillary palp contact. The palp surface is densely covered with sensilla, and internally the tissue displays a complementary distribution of dopaminergic and serotonergic neurons. RNAi assays demonstrated that three <em>GR</em> genes (<em>GR2-like</em>, <em>GR28b-like</em>, and <em>GR64e-like</em>) mediate corpse avoidance. Silencing <em>GR2-like</em> alone significantly reduced avoidance, while simultaneous knockdown of <em>GR28b-like</em> and <em>GR64e-like</em> further weakened the response, suggesting functional interactions among gustatory receptors in <em>H. axyridis</em>. These findings reveal a gustatory mechanism underlying corpse avoidance in predatory insects and provide insights relevant to biological control and artificial diet development.</div></div>\",\"PeriodicalId\":16189,\"journal\":{\"name\":\"Journal of insect physiology\",\"volume\":\"166 \",\"pages\":\"Article 104886\"},\"PeriodicalIF\":2.3000,\"publicationDate\":\"2025-09-17\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of insect physiology\",\"FirstCategoryId\":\"97\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022191025001404\",\"RegionNum\":2,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENTOMOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of insect physiology","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022191025001404","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENTOMOLOGY","Score":null,"Total":0}
The ladybird Harmonia axyridis is an important predatory natural enemy with a broad dietary spectrum and few avoided food sources. Nevertheless, it shows avoidance behavior toward aphid corpses, likely to minimize the risk of pathogen infection in the wild. The molecular basis of this behavior remains unclear, and gustatory receptors (GRs) are hypothesized to be involved. Here, we examined the avoidance of H. axyridis toward pea aphid (Acyrthosiphon pisum) corpses and investigated the role of candidate GR genes in contact chemoreception via the maxillary palps. Using SEM and immunofluorescence, we characterized the microstructure of the maxillary palps and mapped neuronal distributions. Behavioral assays combined with RNAi were performed to evaluate three candidate GR genes associated with corpse recognition. Our results show that feeding behavior on A. pisum is largely determined by gustatory input through maxillary palp contact. The palp surface is densely covered with sensilla, and internally the tissue displays a complementary distribution of dopaminergic and serotonergic neurons. RNAi assays demonstrated that three GR genes (GR2-like, GR28b-like, and GR64e-like) mediate corpse avoidance. Silencing GR2-like alone significantly reduced avoidance, while simultaneous knockdown of GR28b-like and GR64e-like further weakened the response, suggesting functional interactions among gustatory receptors in H. axyridis. These findings reveal a gustatory mechanism underlying corpse avoidance in predatory insects and provide insights relevant to biological control and artificial diet development.
期刊介绍:
All aspects of insect physiology are published in this journal which will also accept papers on the physiology of other arthropods, if the referees consider the work to be of general interest. The coverage includes endocrinology (in relation to moulting, reproduction and metabolism), pheromones, neurobiology (cellular, integrative and developmental), physiological pharmacology, nutrition (food selection, digestion and absorption), homeostasis, excretion, reproduction and behaviour. Papers covering functional genomics and molecular approaches to physiological problems will also be included. Communications on structure and applied entomology can be published if the subject matter has an explicit bearing on the physiology of arthropods. Review articles and novel method papers are also welcomed.