Pub Date : 2026-04-01Epub Date: 2026-01-29DOI: 10.1016/j.ibmb.2026.104503
Fu Cao , Hongfei Li , Bao Dong , Yuanyuan Peng , Li Xu , Shifan Li , Jinjun Wang , Hongbo Jiang
The oriental fruit fly, Bactrocera dorsalis is a serious fruit pest. Trimethylpyrazine (TMP) and tetramethylpyrazine (TTMP) were characterized as its male released sex pheromone, which showed strong attraction to sexually mature females. So far, the molecular basis of the perception of TMP and TTMP by the females has remained unknown. In this study, using BdorIR8a−/− and BdorOrco−/− mutants, we demonstrated that the perception of TMP and TTMP is mediated by odorant receptors (ORs). Furthermore, we generated transgenic Drosophila expressing two odorant receptors (BdorOR49a and BdorOR63a previously showed in vitro binding ability to TMP and TTMP, respectively) in T1 neurons. Subsequent single sensillum recordings (SSR) of the transgenic fly demonstrated that BdorOR49a and BdorOR63a are tuned to TMP and TTMP, respectively. Furthermore, knockout of BdorOR49a and knockdown of BdorOR63a in vivo reduced the olfactory sensitivity of the females to TMP and TTMP. Our results indicated that BdorOR49a and BdorOR63a are responsible for the perception of the male released sex pheromones in B. dorsalis.
{"title":"BdorOR49a and BdorOR63a are responsible for male pheromones perception in the oriental fruit fly","authors":"Fu Cao , Hongfei Li , Bao Dong , Yuanyuan Peng , Li Xu , Shifan Li , Jinjun Wang , Hongbo Jiang","doi":"10.1016/j.ibmb.2026.104503","DOIUrl":"10.1016/j.ibmb.2026.104503","url":null,"abstract":"<div><div>The oriental fruit fly, <em>Bactrocera dorsalis</em> is a serious fruit pest. Trimethylpyrazine (TMP) and tetramethylpyrazine (TTMP) were characterized as its male released sex pheromone, which showed strong attraction to sexually mature females. So far, the molecular basis of the perception of TMP and TTMP by the females has remained unknown. In this study, using <em>BdorIR8a</em><sup><em>−/−</em></sup> and <em>BdorOrco</em><sup><em>−/−</em></sup> mutants, we demonstrated that the perception of TMP and TTMP is mediated by odorant receptors (ORs). Furthermore, we generated transgenic <em>Drosophila</em> expressing two odorant receptors (<em>BdorOR49a</em> and <em>BdorOR63a</em> previously showed <em>in vitro</em> binding ability to TMP and TTMP, respectively) in T1 neurons. Subsequent single sensillum recordings (SSR) of the transgenic fly demonstrated that <em>BdorOR49a</em> and <em>BdorOR63a</em> are tuned to TMP and TTMP, respectively. Furthermore, knockout of <em>BdorOR49a</em> and knockdown of <em>BdorOR63a in vivo</em> reduced the olfactory sensitivity of the females to TMP and TTMP. Our results indicated that <em>BdorOR49a</em> and <em>BdorOR63a</em> are responsible for the perception of the male released sex pheromones in <em>B</em>. <em>dorsalis</em>.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104503"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146096881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-06DOI: 10.1016/j.ibmb.2026.104515
Shi-Hong Gu
Autocrine activation of ecdysteroidogenesis in the prothoracic glands (PGs) of the silkworm, Bombyx mori, was previously demonstrated. In the present study, the signaling cascade involved in this autocrine activation was further investigated. I found that phosphorylation of the translational repressor 4E-binding protein (4E-BP) increased in a time-dependent manner when PGs were incubated in a small volume (10 μl) of medium, compared to those incubated in a larger volume (100 μl). Higher levels of 4E-BP phosphorylation were also observed in PGs incubated either in PG-conditioned medium or under group incubation conditions. Treatment with LY294002 and rapamycin reduced 4E-BP phosphorylation, indicating the involvement of the PI3K/TOR pathway. I further investigated the downstream target genes involved in autocrine activation. Results showed that the expression levels of several sugar transporter (St) and trehalase (Treh) genes were upregulated in PGs incubated in a small volume (10 μl) of medium. Treatment with LY294002 and rapamycin suppressed the autocrine activation of St1 and Treh1 expressions, suggesting that their regulation is mediated via the PI3K/TOR pathway. Time-dependent autocrine activation of Treh enzyme activity was observed, and this effect was blocked by pretreatment with validamycin A, a specific Treh inhibitor, suggesting that the autocrine factor directly enhances Treh activity. Treatment with either validamycin A or the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) suppressed autocrine activation of ecdysteroidogenesis, clearly indicating that both Treh activity and glycolysis are involved. To investigate potential upstream ligands, I examined the gene expressions of bombyxins and epidermal growth factor (Egf) signaling components. Results showed that only bombyxin-Z1 expression was upregulated in a time-dependent manner under an autocrine condition, while other genes remained unchanged. Using a specifically generated anti-bombyxin-Z1 antibody, the presence of bombyxin-Z1 protein was confirmed. To my knowledge, this is the first study to elucidate the signaling cascade involved in autocrine activation of ecdysteroidogenesis in an insect system.
{"title":"Signaling pathway underlying autocrine activation of ecdysteroidogenesis in prothoracic glands of Bombyx mori","authors":"Shi-Hong Gu","doi":"10.1016/j.ibmb.2026.104515","DOIUrl":"10.1016/j.ibmb.2026.104515","url":null,"abstract":"<div><div>Autocrine activation of ecdysteroidogenesis in the prothoracic glands (PGs) of the silkworm, <em>Bombyx mori</em>, was previously demonstrated. In the present study, the signaling cascade involved in this autocrine activation was further investigated. I found that phosphorylation of the translational repressor 4E-binding protein (4E-BP) increased in a time-dependent manner when PGs were incubated in a small volume (10 μl) of medium, compared to those incubated in a larger volume (100 μl). Higher levels of 4E-BP phosphorylation were also observed in PGs incubated either in PG-conditioned medium or under group incubation conditions. Treatment with LY294002 and rapamycin reduced 4E-BP phosphorylation, indicating the involvement of the PI3K/TOR pathway. I further investigated the downstream target genes involved in autocrine activation. Results showed that the expression levels of several <em>sugar transporter</em> (<em>St</em>) and <em>trehalase</em> (<em>Treh</em>) genes were upregulated in PGs incubated in a small volume (10 μl) of medium. Treatment with LY294002 and rapamycin suppressed the autocrine activation of <em>St1</em> and <em>Treh1</em> expressions, suggesting that their regulation is mediated via the PI3K/TOR pathway. Time-dependent autocrine activation of Treh enzyme activity was observed, and this effect was blocked by pretreatment with validamycin A, a specific Treh inhibitor, suggesting that the autocrine factor directly enhances Treh activity. Treatment with either validamycin A or the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) suppressed autocrine activation of ecdysteroidogenesis, clearly indicating that both Treh activity and glycolysis are involved. To investigate potential upstream ligands, I examined the gene expressions of <em>bombyxins</em> and epidermal growth factor (Egf) signaling components. Results showed that only <em>bombyxin-Z1</em> expression was upregulated in a time-dependent manner under an autocrine condition, while other genes remained unchanged. Using a specifically generated anti-bombyxin-Z1 antibody, the presence of bombyxin-Z1 protein was confirmed. To my knowledge, this is the first study to elucidate the signaling cascade involved in autocrine activation of ecdysteroidogenesis in an insect system.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104515"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146136993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-21DOI: 10.1016/j.ibmb.2026.104498
Antonio Mocchetti , Pieter Steelant , Mahboubeh Hosseinkhani , Sander De Rouck , Jahangir Khajehali , Thomas Van Leeuwen
Spinosyns are allosteric modulators of nicotinic acetylcholine receptors (nAChRs) which in insects specifically target subunit α6. However, their mode of action in mites and compatibility with phytoseiid predators remain unclear. We combined phylogenetics with CRISPR/Cas-based reverse genetics to test whether α6-like subunits mediate spinosyn toxicity in mites and to assess prospects for resistance breeding in phytoseiids. The phylogenetic analysis identified seven α and three β subunits in multiple phytoseiids and in Tetranychus urticae. A single phytoseiid subunit clustered within the insect α6/α7 clade, whereas T. urticae possessed three (Tuα5/α6/α7) without strict one-to-one insect orthology. Using SYNCAS maternal delivery of CRISPR RNPs, we disrupted the putative α6 ortholog in Amblyseius swirskii (Asα6) and each of the three α6/α7-clade genes in T. urticae. In A. swirskii, all survivors of a discriminating spinosad dose carried Asα6 indels, and three independently edited lines exhibited insensitivity to both spinosad and spinetoram (no significant mortality at 10 000 mg a.i./L), whereas the wild type showed LC50 = 163 mg/L (spinosad) and 54 mg/L (spinetoram). In T. urticae, Tuα6 knockouts conferred high cross-resistance to both compounds, while Tuα5 knockouts slightly increased susceptibility and Tuα7 knockouts produced modest resistance. Our data demonstrate that α6-mediated spinosyn action is conserved in mites, with α6 loss conferring strong cross-resistance in a key phytoseiid predator and in a model tetranychid. These findings enable marker-assisted editing/selection of spinosyn-resistant phytoseiid strains to improve pesticide–biocontrol compatibility and establish α6 as a practical universal marker gene for genome editing in acarine systems.
{"title":"Knockout of nAChR subunits in spider mites and their phytoseiid predators confers spinosyn cross-resistance and reveals a conserved mode of action in mites","authors":"Antonio Mocchetti , Pieter Steelant , Mahboubeh Hosseinkhani , Sander De Rouck , Jahangir Khajehali , Thomas Van Leeuwen","doi":"10.1016/j.ibmb.2026.104498","DOIUrl":"10.1016/j.ibmb.2026.104498","url":null,"abstract":"<div><div>Spinosyns are allosteric modulators of nicotinic acetylcholine receptors (nAChRs) which in insects specifically target subunit α6. However, their mode of action in mites and compatibility with phytoseiid predators remain unclear. We combined phylogenetics with CRISPR/Cas-based reverse genetics to test whether α6-like subunits mediate spinosyn toxicity in mites and to assess prospects for resistance breeding in phytoseiids. The phylogenetic analysis identified seven α and three β subunits in multiple phytoseiids and in <em>Tetranychus urticae</em>. A single phytoseiid subunit clustered within the insect α6/α7 clade, whereas <em>T. urticae</em> possessed three (Tuα5/α6/α7) without strict one-to-one insect orthology. Using SYNCAS maternal delivery of CRISPR RNPs, we disrupted the putative α6 ortholog in <em>Amblyseius swirskii</em> (Asα6) and each of the three α6/α7-clade genes in <em>T. urticae</em>. In <em>A. swirskii</em>, all survivors of a discriminating spinosad dose carried Asα6 indels, and three independently edited lines exhibited insensitivity to both spinosad and spinetoram (no significant mortality at 10 000 mg a.i./L), whereas the wild type showed LC<sub>50</sub> = 163 mg/L (spinosad) and 54 mg/L (spinetoram). In <em>T. urticae</em>, Tuα6 knockouts conferred high cross-resistance to both compounds, while Tuα5 knockouts slightly increased susceptibility and Tuα7 knockouts produced modest resistance. Our data demonstrate that α6-mediated spinosyn action is conserved in mites, with α6 loss conferring strong cross-resistance in a key phytoseiid predator and in a model tetranychid. These findings enable marker-assisted editing/selection of spinosyn-resistant phytoseiid strains to improve pesticide–biocontrol compatibility and establish α6 as a practical universal marker gene for genome editing in acarine systems.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104498"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146040050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-02DOI: 10.1016/j.ibmb.2026.104514
Yinghui Zhou , Yunxuan Chen , Chanuka Wijewardana , Chenxuan Jiang , Yuhan Guo , Donghui Zhang , Min Hou , Zhipeng Xu , Lu Chen , MinJun Ji , Lin Chen
Mosquito-borne diseases persist as a critical global health burden, driving the demand for novel vector control approaches. Here, we identify and characterize Pipiserpin, a female-specific serine protease inhibitor (serpin) in Culex pipiens pallens, and elucidate its role in regulating reproductive fitness. Pipiserpin exhibits tissue-specific expression in the fat body and ovary, peaking post-blood meal, and features a conserved serpin fold with a reactive central loop critical for protease inhibition. RNA interference-mediated knockdown of Pipiserpin severely impaired ovarian follicular development, reducing follicle size by 7.73% and egg production by 68.10%. Mechanistically, Pipiserpin depletion destabilized vitellogenin (Vg)—a key yolk precursor—by 62.79% in the fat body and 73.01% in the ovary, despite unchanged Vg transcription. This phenotype was attributed to unchecked trypsin-mediated Vg degradation, as demonstrated by recombinant Pipiserpin's dose-dependent inhibition of trypsin activity. Crucially, exogenous 20-hydroxyecdysone (20E) supplementation restored Vg protein levels, follicular maturation and fecundity, revealing a compensatory relationship wherein the 20E-Vg hormonal pathway can functionally overcome reproductive defects caused by Pipiserpin depletion. Global transcriptomic profiling of Pipiserpin-depleted mosquitoes identified 221 differentially expressed genes, including upregulated trypsin-like proteases and metabolic pathway components, indicative of disrupted proteolytic balance and compensatory metabolic remodeling. Our findings redefine serpin functionality in arthropods, highlighting Pipiserpin's dual role in post-translational Vg stabilization and crosstalk with developmental signaling. This work positions Pipiserpin as a promising target for RNAi or small-molecule interventions to disrupt mosquito reproduction, offering a sustainable strategy for combating vector-borne diseases by precisely targeting reproduction.
{"title":"Pipiserpin orchestrates mosquito reproduction through dual control of vitellogenin integrity and 20-hydroxyecdysone-directed vitellogenesis","authors":"Yinghui Zhou , Yunxuan Chen , Chanuka Wijewardana , Chenxuan Jiang , Yuhan Guo , Donghui Zhang , Min Hou , Zhipeng Xu , Lu Chen , MinJun Ji , Lin Chen","doi":"10.1016/j.ibmb.2026.104514","DOIUrl":"10.1016/j.ibmb.2026.104514","url":null,"abstract":"<div><div>Mosquito-borne diseases persist as a critical global health burden, driving the demand for novel vector control approaches. Here, we identify and characterize Pipiserpin, a female-specific serine protease inhibitor (serpin) in <em>Culex pipiens pallens</em>, and elucidate its role in regulating reproductive fitness. Pipiserpin exhibits tissue-specific expression in the fat body and ovary, peaking post-blood meal, and features a conserved serpin fold with a reactive central loop critical for protease inhibition. RNA interference-mediated knockdown of Pipiserpin severely impaired ovarian follicular development, reducing follicle size by 7.73% and egg production by 68.10%. Mechanistically, Pipiserpin depletion destabilized vitellogenin (Vg)—a key yolk precursor—by 62.79% in the fat body and 73.01% in the ovary, despite unchanged Vg transcription. This phenotype was attributed to unchecked trypsin-mediated Vg degradation, as demonstrated by recombinant Pipiserpin's dose-dependent inhibition of trypsin activity. Crucially, exogenous 20-hydroxyecdysone (20E) supplementation restored Vg protein levels, follicular maturation and fecundity, revealing a compensatory relationship wherein the 20E-Vg hormonal pathway can functionally overcome reproductive defects caused by Pipiserpin depletion. Global transcriptomic profiling of Pipiserpin-depleted mosquitoes identified 221 differentially expressed genes, including upregulated trypsin-like proteases and metabolic pathway components, indicative of disrupted proteolytic balance and compensatory metabolic remodeling. Our findings redefine serpin functionality in arthropods, highlighting Pipiserpin's dual role in post-translational Vg stabilization and crosstalk with developmental signaling. This work positions Pipiserpin as a promising target for RNAi or small-molecule interventions to disrupt mosquito reproduction, offering a sustainable strategy for combating vector-borne diseases by precisely targeting reproduction.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104514"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146117235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The tomato leaf miner (Tuta absoluta) is a globally destructive pest that cause extensive damage to tomato crops by chewing mouthparts, leading to severe necrosis, fruit abortion, and substantial yield losses. To date, the elicitors/effectors of T. absoluta have not been characterized. In this study, we combined proteomic profiling of T. absoluta-infested tomato leaves with transcriptomic analysis of salivary glands to identify candidate molecules involved in herbivory-driven plant responses. Bioinformatics analyses predicted 40 candidate elicitors and effectors, which were subsequently assessed through transient expression assays in Nicotiana benthamiana. The results demonstrated that the candidate number 33 (T. absoluta 33, Ta33) induced cell death in both the intracellular space and the apoplast, while Ta21 triggered a strong apoplastic reactive oxygen species (ROS) burst. Conversely, Ta38 effectively suppressed INF1-induced cell death. Quantitative real-time PCR analysis further showed that these genes were highly expressed during the feeding stage, supporting their involvement in plant–insect molecular dialogue. This study systematically identified and characterized elicitors and effectors of T. absoluta, providing a foundational framework for elucidating its herbivory mechanisms and developing targeted management strategies.
{"title":"Identification of tomato leaf miner secretory proteins and their roles in influencing plant defenses","authors":"Yumei Dong , Guolan Wu , Qiuyun Zhang , Zhili Zhao , Yunhua Zhang , Qian Li , Chuanlin Yin , Pengjun Zhang","doi":"10.1016/j.ibmb.2026.104500","DOIUrl":"10.1016/j.ibmb.2026.104500","url":null,"abstract":"<div><div>The tomato leaf miner (<em>Tuta absoluta</em>) is a globally destructive pest that cause extensive damage to tomato crops by chewing mouthparts, leading to severe necrosis, fruit abortion, and substantial yield losses. To date, the elicitors/effectors of <em>T. absoluta</em> have not been characterized. In this study, we combined proteomic profiling of <em>T. absoluta</em>-infested tomato leaves with transcriptomic analysis of salivary glands to identify candidate molecules involved in herbivory-driven plant responses. Bioinformatics analyses predicted 40 candidate elicitors and effectors, which were subsequently assessed through transient expression assays in <em>Nicotiana benthamiana</em>. The results demonstrated that the candidate number 33 (<em>T</em>. <em>absoluta</em> 33, Ta33) induced cell death in both the intracellular space and the apoplast, while Ta21 triggered a strong apoplastic reactive oxygen species (ROS) burst. Conversely, Ta38 effectively suppressed INF1-induced cell death. Quantitative real-time PCR analysis further showed that these genes were highly expressed during the feeding stage, supporting their involvement in plant–insect molecular dialogue. This study systematically identified and characterized elicitors and effectors of <em>T. absoluta</em>, providing a foundational framework for elucidating its herbivory mechanisms and developing targeted management strategies.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104500"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146057322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-29DOI: 10.1016/j.ibmb.2026.104502
Lautaro Gandara , Felipe Martelli , Thomas Ravenscroft , Justin Crocker , Philip Batterham
Insecticides remain indispensable for crop protection and food security, yet their widespread use may contribute to the global decline of beneficial insect populations. Efforts to mitigate these impacts are hampered by a fragmented understanding of how insects metabolise insecticides and how sublethal exposures affect physiology, behaviour, and fitness. Here, we synthesise current understanding of metabolic detoxification and highlight critical gaps: the tissue- and time-dependent dynamics of insecticide entry and processing, the triggers and architecture of xenobiotic transcriptional responses, the role of rapid non-transcriptional regulation, and the population-level consequences of sublethal effects. We also outline emerging experimental strategies for addressing these questions and propose a next-generation research pipeline centred on multi-endpoint phenomics across life stages and sentinel species, integrated with AI-driven predictive toxicology, as a framework for identifying safer chemicals. We propose an integrated framework unifying molecular, physiological, and ecological responses to sublethal exposure to guide the design of insecticides that maintain effective pest control while safeguarding insect biodiversity and the ecosystems it underpins.
{"title":"Rethinking insecticide toxicology for the 21st century","authors":"Lautaro Gandara , Felipe Martelli , Thomas Ravenscroft , Justin Crocker , Philip Batterham","doi":"10.1016/j.ibmb.2026.104502","DOIUrl":"10.1016/j.ibmb.2026.104502","url":null,"abstract":"<div><div>Insecticides remain indispensable for crop protection and food security, yet their widespread use may contribute to the global decline of beneficial insect populations. Efforts to mitigate these impacts are hampered by a fragmented understanding of how insects metabolise insecticides and how sublethal exposures affect physiology, behaviour, and fitness. Here, we synthesise current understanding of metabolic detoxification and highlight critical gaps: the tissue- and time-dependent dynamics of insecticide entry and processing, the triggers and architecture of xenobiotic transcriptional responses, the role of rapid non-transcriptional regulation, and the population-level consequences of sublethal effects. We also outline emerging experimental strategies for addressing these questions and propose a next-generation research pipeline centred on multi-endpoint phenomics across life stages and sentinel species, integrated with AI-driven predictive toxicology, as a framework for identifying safer chemicals. We propose an integrated framework unifying molecular, physiological, and ecological responses to sublethal exposure to guide the design of insecticides that maintain effective pest control while safeguarding insect biodiversity and the ecosystems it underpins.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104502"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146096655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
RNA interference (RNAi) is a conserved gene-silencing mechanism; however, its efficiency varies among insect taxa and is particularly low in lepidopterans. A Lepidoptera-specific nuclease, RNAi efficiency-related nuclease (REase), has recently been identified as an RNAi suppressor that degrades double-stranded RNA (dsRNA) upon exposure. To investigate the diversity and potential functions of the REase genes, a phylogenetic analysis was conducted across lepidopteran species and a gene expression analysis of Spodoptera exigua was performed. Three lepidopteran-specific REase groups (REase1–3) and one conserved group related to Asteroids were identified, with all previously reported REase genes classified as REase1. REase3 likely originated from an ancestral duplication of an Asteroid, from which REase1 and REase2 subsequently diverged. REase1 and REase2 were broadly distributed across Lepidoptera, although absent in some lineages. Notably, REase1 exhibited extensive copy number variation among species, whereas REase2 and REase3 were mostly in single-copy form. Expression analysis showed that both REase1 and REase2 were strongly upregulated following dsRNA injection, along with core RNAi components such as Dicer2 and Argonaute2. This dsRNA responsiveness, combined with the accelerated evolution of the REases, suggests their involvement in an evolutionary arms race involving fast-evolving immune challenges, such as viruses. Furthermore, the rapid evolution and frequent gene loss of REase paralogs, which are hallmarks of functionally redundant genes, suggest that REase2 acts as an RNAi suppressor, similar to REase1. These findings highlight the evolutionary diversity and possible functional redundancy of the REases and underscore their potential importance in modulating RNAi efficiency in Lepidoptera.
{"title":"Diversity of RNAi efficiency-related nuclease in lepidopteran insects","authors":"Keisuke Nagamine, Takumi Kayukawa, Kazuyo Watanabe, Yoshiaki Tanaka","doi":"10.1016/j.ibmb.2026.104501","DOIUrl":"10.1016/j.ibmb.2026.104501","url":null,"abstract":"<div><div>RNA interference (RNAi) is a conserved gene-silencing mechanism; however, its efficiency varies among insect taxa and is particularly low in lepidopterans. A Lepidoptera-specific nuclease, RNAi efficiency-related nuclease (REase), has recently been identified as an RNAi suppressor that degrades double-stranded RNA (dsRNA) upon exposure. To investigate the diversity and potential functions of the REase genes, a phylogenetic analysis was conducted across lepidopteran species and a gene expression analysis of <em>Spodoptera exigua</em> was performed. Three lepidopteran-specific REase groups (REase1–3) and one conserved group related to Asteroids were identified, with all previously reported REase genes classified as REase1. REase3 likely originated from an ancestral duplication of an Asteroid, from which REase1 and REase2 subsequently diverged. REase1 and REase2 were broadly distributed across Lepidoptera, although absent in some lineages. Notably, REase1 exhibited extensive copy number variation among species, whereas REase2 and REase3 were mostly in single-copy form. Expression analysis showed that both <em>REase1</em> and <em>REase2</em> were strongly upregulated following dsRNA injection, along with core RNAi components such as <em>Dicer2</em> and <em>Argonaute2</em>. This dsRNA responsiveness, combined with the accelerated evolution of the REases, suggests their involvement in an evolutionary arms race involving fast-evolving immune challenges, such as viruses. Furthermore, the rapid evolution and frequent gene loss of REase paralogs, which are hallmarks of functionally redundant genes, suggest that REase2 acts as an RNAi suppressor, similar to REase1. These findings highlight the evolutionary diversity and possible functional redundancy of the REases and underscore their potential importance in modulating RNAi efficiency in Lepidoptera.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104501"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146083525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-18DOI: 10.1016/j.ibmb.2026.104519
Zhuorui Li , Yanmei He , Yan Shen , Miao He , Ting Lin , Jiayi Yang , Lixian Mu , Jing Wu , Hailong Yang
While Kazal-type inhibitors from hematophagous animals are well-known anticoagulants, their roles in platelet regulation remain largely unexplored. Here, we report the characterization of Sibakazin, a single-domain Kazal-type inhibitor from the salivary glands of the blood-sucking black fly Simulium bannaense. Structurally, Sibakazin possesses a non-canonical acidic N-terminus and methionine at the P1 site. Consistent with this distinctive structure, Sibakazin exhibited no activity against key serine proteases of the coagulation cascade (e.g., thrombin, FXa) and did not affect clotting times (aPTT, PT), distinguishing it from classical anticoagulants. Intriguingly, Sibakazin demonstrated potent antithrombotic efficacy in vivo, suppressing both FeCl3-induced arterial and carrageenan-induced venous thrombosis in mice without increasing bleeding risk. Mechanistically, Sibakazin exerts its effects through dual inhibition of platelet activation. It directly targets glycoprotein VI (GPVI), suppressing the downstream Src/Syk/PLCγ2/Akt signaling cascade to block thrombus initiation, while simultaneously inhibiting the ADP receptor P2Y12, disrupting the PI3K/Akt pathway to attenuate secondary amplification signals. This dual blockade effectively inhibits platelet aggregation, spreading, and clot retraction. Our findings identify Sibakazin as a novel dual-targeting antiplatelet agent with potent safe antithrombotic properties, expanding the functional landscape of Kazal-type inhibitors and providing a promising contribution for next generation therapeutic development.
{"title":"Sibakazin: a novel black fly derived non-classical kazal protease inhibitor, targeting antiplatelet (P2Y12/GPVI) pathways without perturbing coagulation","authors":"Zhuorui Li , Yanmei He , Yan Shen , Miao He , Ting Lin , Jiayi Yang , Lixian Mu , Jing Wu , Hailong Yang","doi":"10.1016/j.ibmb.2026.104519","DOIUrl":"10.1016/j.ibmb.2026.104519","url":null,"abstract":"<div><div>While Kazal-type inhibitors from hematophagous animals are well-known anticoagulants, their roles in platelet regulation remain largely unexplored. Here, we report the characterization of Sibakazin, a single-domain Kazal-type inhibitor from the salivary glands of the blood-sucking black fly <em>Simulium bannaense</em>. Structurally, Sibakazin possesses a non-canonical acidic N-terminus and methionine at the P1 site. Consistent with this distinctive structure, Sibakazin exhibited no activity against key serine proteases of the coagulation cascade (e.g., thrombin, FXa) and did not affect clotting times (aPTT, PT), distinguishing it from classical anticoagulants. Intriguingly, Sibakazin demonstrated potent antithrombotic efficacy in vivo, suppressing both FeCl<sub>3</sub>-induced arterial and carrageenan-induced venous thrombosis in mice without increasing bleeding risk. Mechanistically, Sibakazin exerts its effects through dual inhibition of platelet activation. It directly targets glycoprotein VI (GPVI), suppressing the downstream Src/Syk/PLCγ2/Akt signaling cascade to block thrombus initiation, while simultaneously inhibiting the ADP receptor P2Y12, disrupting the PI3K/Akt pathway to attenuate secondary amplification signals. This dual blockade effectively inhibits platelet aggregation, spreading, and clot retraction. Our findings identify Sibakazin as a novel dual-targeting antiplatelet agent with potent safe antithrombotic properties, expanding the functional landscape of Kazal-type inhibitors and providing a promising contribution for next generation therapeutic development.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104519"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146256855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-02-20DOI: 10.1016/j.ibmb.2026.104520
Ken Narva , Eric Gordon , Emre İnak , Steven Smith , Sean Whipple , Brian Manley , Joseane Moreira do Nascimento , Vladimir Zhurov , Vinayak Singh , Kristie Bruinsma , Nafiye Koç-İnak , Miodrag Grbic , Umut Toprak , Vojislava Grbic
Mites cause significant agricultural losses by feeding directly on crops and indirectly by reducing pollination services due to the negative impacts of honey bee parasites on apiary health. Further, mites are notorious for developing resistance to chemical control methods, creating an urgent need for new mode of action acaricides to be used in integrated pest management programs. Over the past decade, significant efforts to develop RNAi-based acaricides for agriculturally important herbivorous and parasitic mites have led to translation of basic research, representing potentially new solutions for growers and beekeepers. The availability of high-quality genome data has enabled the identification of mite gene target sequences sensitive to RNAi that limit impacts on beneficial organisms. Detailed studies of RNAi processes in mites have informed the development of practical methods for controlling mites in the field. Recent development of low-cost, large-scale dsRNA production, once a significant barrier to sprayable RNA products, has provided a springboard to advance RNAi miticides into commercial development. Here we review progress made to date in developing RNAi-based acaricides as new mode of action tools for controlling agriculturally important spider mites and the bee parasite Varroa destructor.
{"title":"RNAi-based acaricides: On the Path to commercialization of new tools for mite management in crops and hives","authors":"Ken Narva , Eric Gordon , Emre İnak , Steven Smith , Sean Whipple , Brian Manley , Joseane Moreira do Nascimento , Vladimir Zhurov , Vinayak Singh , Kristie Bruinsma , Nafiye Koç-İnak , Miodrag Grbic , Umut Toprak , Vojislava Grbic","doi":"10.1016/j.ibmb.2026.104520","DOIUrl":"10.1016/j.ibmb.2026.104520","url":null,"abstract":"<div><div>Mites cause significant agricultural losses by feeding directly on crops and indirectly by reducing pollination services due to the negative impacts of honey bee parasites on apiary health. Further, mites are notorious for developing resistance to chemical control methods, creating an urgent need for new mode of action acaricides to be used in integrated pest management programs. Over the past decade, significant efforts to develop RNAi-based acaricides for agriculturally important herbivorous and parasitic mites have led to translation of basic research, representing potentially new solutions for growers and beekeepers. The availability of high-quality genome data has enabled the identification of mite gene target sequences sensitive to RNAi that limit impacts on beneficial organisms. Detailed studies of RNAi processes in mites have informed the development of practical methods for controlling mites in the field. Recent development of low-cost, large-scale dsRNA production, once a significant barrier to sprayable RNA products, has provided a springboard to advance RNAi miticides into commercial development. Here we review progress made to date in developing RNAi-based acaricides as new mode of action tools for controlling agriculturally important spider mites and the bee parasite <em>Varroa destructor</em>.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"189 ","pages":"Article 104520"},"PeriodicalIF":3.7,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147269319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}