Insect Biochemistry and Molecular Biology最新文献

{"title":"Mini-review: Aspects of cuticle formation and structure advanced by studies in Nilaparvata lugens.","authors":"Chuan-Xi Zhang, Bernard Moussian","doi":"10.1016/j.ibmb.2025.104326","DOIUrl":"https://doi.org/10.1016/j.ibmb.2025.104326","url":null,"abstract":"<p><p>A hallmark of insects is their cuticle that protects them against predators and parasites, prevents desiccation and xenobiotic penetration and, finally, serves locomotion as an exoskeleton. In the last two decades, tremendous efforts have yielded a plethora of molecular and histological data that have boosted our understanding of the mechanisms of cuticle formation and function. As the factors involved in cuticle formation and function are to a large extent specific to insects, these data may be used in intelligent pest management strategies. The brown planthopper Nilaparvata lugens is a major rice pest in Asia. Cuticle research in this species has been following findings in other insect species recapitulating most collected results. There are, in addition, several important data in N. lugens that advanced our understanding in cuticle biology in insects generally. For instance, it was demonstrated in the brown planthopper that a chitin-binding protein, namely NlugCpr47 is needed for organ shaping. Moreover, based on genetic data, it was hypothesised that cuticular lipids may be organised in layers depending on the size of the molecules. Finally, pore canals, the nanotubes system that is used as a transport route for cuticle lipid deposition, were visualised in 3D with high resolution for the first time in an insect. These examples, reviewed in this article, underline the importance of a detailed molecular and histological approach in non-model insects for a better understanding of cuticle biology in general.</p>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":" ","pages":"104326"},"PeriodicalIF":3.2,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144085550","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}

{"title":"Sex-biased fertility degeneration induced by depletion of an auxiliary piRNA-pathway factor Qin in Bombyx mori","authors":"Kai Chen ,&nbsp;Ling Ye ,&nbsp;Ye Yu ,&nbsp;Peilin Guo ,&nbsp;Anjiang Tan","doi":"10.1016/j.ibmb.2025.104319","DOIUrl":"10.1016/j.ibmb.2025.104319","url":null,"abstract":"<div><div>The PIWI-interacting RNA (piRNA) pathway is the major defense system for transposable elements (TEs) silencing in animal gonads, maintaining genomic integrity of germ cells and ensuring proper gametogenesis. An the piRNA-pathway factor, <em>Qin</em>, has been reported to participate in piRNA biogenesis in the lepidopteran model insect, <em>Bombyx mori</em>. Nevertheless, the physiological functions of <em>Qin</em> remain to be characterized. Here we demonstrated that Qin plays important roles in silkworm gonad development of both sexes. <em>BmQin</em> was predominantly expressed in gonads. Immunofluorescent staining revealed that BmQin is localized in the cytoplasm of both germ cells and somatic cells in gonads. Depletion of <em>BmQin</em> via CRISPR/Cas9 system induceed complete sterile in males, and partial sterile in females. Notably, mutants displayed severe defects in gonad development and gametogenesis. RNA-seq analysis revealed that the piRNA pathway was dysregulated in mutant gonads. In addition, apoptosis was significantly enhanced in mutant gonads. Our study revealed the physiological functions of <em>BmQin</em> in silkworm fertility and its auxiliary roles in the piRNA pathway in both male and female gonads.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"181 ","pages":"Article 104319"},"PeriodicalIF":3.2,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143928346","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}

{"title":"Molecular mechanisms based on peripheral level of vanillin recognition in Orthaga achatina (Lepidoptera: Pyralidae)","authors":"Ting-Ting Yang ,&nbsp;Yu Ma ,&nbsp;Zheng Dai ,&nbsp;Ying Li ,&nbsp;Ji-Xiang Wang ,&nbsp;Teng-Fei Bai ,&nbsp;Merid Negash Getahun ,&nbsp;George F.O. Obiero ,&nbsp;Shuang-Lin Dong ,&nbsp;Jin Zhang ,&nbsp;Qi Yan","doi":"10.1016/j.ibmb.2025.104317","DOIUrl":"10.1016/j.ibmb.2025.104317","url":null,"abstract":"<div><div><em>Orthaga achatina</em> (Lepidoptera Pyralidae) is a specialist pest of the camphor tree <em>Cinnamomum camphora</em>. Vanillin is a volatile compound found in many plants, and its effects on insects can be either attractive or repellent, depending on the species. However, the behavioral response of <em>Orthaga achatina</em> to vanillin, a volatile compound emitted by camphor trees, remains unexplored. In this study, we found that vanillin attracts both male and female <em>O. achatina</em> adults. Fluorescence competitive binding assays further revealed that among the five odorant-binding proteins (OBPs) highly expressed in both male and female antennae, OachOBP7 exhibited the most prominent binding affinity with vanillin. Furthermore, by employing the Xenopus oocyte expression and two-electrode voltage clamp recording system (XOE-TEVC) to conduct a functional characterization of 40 ORs, vanillin was the optimal ligand for OachOR7 among all tested ligands. In addition, with the 3D structure modeling and molecular docking techniques, it was revealed that OachOR7 displayed a relatively high binding affinity (−5.5 kcal/mol), and Gln84 and Asn189 were predicted to be key amino acid residues for binding vanillin. Finally, the two amino acids were verified by site-specific mutagenesis followed by XOE-TEVC, showing that the binding ability of OR7 to vanillin was significantly reduced to 9.23 × 10⁻² μM after the mutation of two amino acids. This study demonstrate vanillin's behavioral attraction to <em>O. achatina</em> and reveal its molecular basis, offering new possibilities for targeted pest management using this compound.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"180 ","pages":"Article 104317"},"PeriodicalIF":3.2,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891843","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}

{"title":"HiHR4 regulates chitin metabolism during molting of Hermetia illucens","authors":"Wei Dong ,&nbsp;Xinyi Wang ,&nbsp;Zining Cheng ,&nbsp;Bernard Moussian ,&nbsp;Jianzhan Zhang ,&nbsp;Xu-Bo Zhang","doi":"10.1016/j.ibmb.2025.104318","DOIUrl":"10.1016/j.ibmb.2025.104318","url":null,"abstract":"<div><div>The black soldier fly (<em>Hermetia illucens</em>) as a model bio-converter insect, is increasingly used in feed formulation and as a fertilizer source. Its growth rate and biomass yield are influenced by molting, a process involving the remodeling of chitinous structures. In this study, we identified a <em>HiHR4</em> gene in <em>Hermetia illucens</em> and report its function in larval growth and molting. RT-qPCR results show that <em>HiHR4</em> expression is stable during the third instar larval stage but peaks sharply prior to molting. Knockdown of <em>HiHR4</em> by RNA interference (RNAi) in larvae results in molting delay. The ds<em>HiHR4-</em>injected larvae display slow growth. Consistently, integument sectioning and chitin staining showed that <em>HiHR4</em> knockdown inhibits both the degradation of the old cuticle and the formation of new cuticle. In addition, <em>HiHR4</em> and chitin metabolism-related genes are induced by the steroid hormone 20-hydroxyecdysone (20E), indicating their responsiveness to 20E signaling. Moreover, <em>HiHR4</em> knockdown significantly suppresses the expression of chitin synthesis genes (<em>HiHex, HiG6PI, HiCHS1</em>) and chitin degradation genes (<em>HiCht10</em>). RNAi against <em>HiCHS1</em> or <em>HiCht10</em> disrupts larval molting and attenuates growth. Taken together, these findings suggest that <em>HiHR4</em> is a key regulator of chitin metabolism, ensuring proper molting and promoting biomass production in <em>H. illucens</em>.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"181 ","pages":"Article 104318"},"PeriodicalIF":3.2,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906452","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}

{"title":"Role of histone methylation in insect development: KMT5A regulates ecdysteroid biosynthesis during metamorphosis of Tribolium castaneum","authors":"Yaoyu Jiao ,&nbsp;Karthi Sengodan,&nbsp;Jiasheng Chen ,&nbsp;Subba Reddy Palli","doi":"10.1016/j.ibmb.2025.104316","DOIUrl":"10.1016/j.ibmb.2025.104316","url":null,"abstract":"<div><div>Methylation levels of core histones play important roles in the regulation of gene expression and impact animal development. However, the methyltransferases and demethylases that determine histone methylation levels remain largely unexplored in insects. Most of our current understanding of histone methylation comes from mammalian studies. In this study, we first identified potential histone methyltransferases and demethylases encoded in the genome of the red flour beetle <em>Tribolium castaneum</em>. The function of these histone methylation enzymes in the metamorphosis was investigated by knocking down genes coding for these enzymes using RNA interference (RNAi). Our results showed that a lysine methyltransferase, KMT5A, plays a critical role in <em>T. castaneum</em> metamorphosis by regulating the biosynthesis of ecdysteroids. Treating <em>KMT5A</em>-knockdown larvae with 20 hydroxyecdysone can partially rescue <em>T. castaneum</em> pupation. Western blot analysis showed that KMT5A catalyzes H4K20 mono-methylation. However, further studies suggest that KMT5A may regulate <em>T. castaneum</em> pupation through mechanisms independent of H4K20 methylation. These data uncovered the roles of histone methylation enzymes in <em>T. castaneum</em> metamorphosis and KMT5A as a critical regulator of ecdysteroid biosynthesis.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"180 ","pages":"Article 104316"},"PeriodicalIF":3.2,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881836","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}

{"title":"The pore canal protein snsl is required for cuticular lipids transport and cuticle barrier function in the migratory locust, Locusta migratoria","authors":"Weimin Liu ,&nbsp;Yiyan Zhao ,&nbsp;Xiaoming Zhao ,&nbsp;Hongfang Guo ,&nbsp;Yang Yang ,&nbsp;Bernard Moussian ,&nbsp;Jianzhen Zhang","doi":"10.1016/j.ibmb.2025.104314","DOIUrl":"10.1016/j.ibmb.2025.104314","url":null,"abstract":"<div><div>Lipids are important components of the insect cuticle protecting against desiccation and xenobiotic penetration. Delivery of lipids to the cuticular surface occurs through pore canals, which are a nano-canal system formed by the epidermis, running through the procuticle and terminating at the epicuticle, where they ramify as wax-canals. The molecular mechanisms of cuticular lipids deposition in insects are poorly understood. Here, we identified the pore canal protein Snsl (Snustorr snarlik) in the migratory locust <em>Locusta migratoria</em> (LmSnsl) and investigated its function in cuticular lipid transport and cuticle barrier construction. We found that <em>LmSnsl</em> was specifically expressed in the integument and had a high expression level before ecdysis when a new cuticle is formed. Silencing of <em>LmSnsl</em> by RNA interference (RNAi) caused a lethal phenotype during or shortly after molting. In addition, RNAi against <em>LmSnsl</em> resulted in a decrease in cuticular lipids and in the accumulation of internal lipids. The pore canals of <em>dsLmSnsl</em> animals are deformed and contain less luminal material. Furthermore, we found that cuticle permeability to xenobiotics was enhanced in ds<em>LmSnsl</em>-treated nymphs that were, consistently, more susceptible to insecticides. These animals were also prone to pathogen invasion suggesting that cuticle lipids act in pathogen defense. Taken together, our results indicate that the locust Snsl protein is needed for pore canal integrity required for the transport of lipids from the epidermis to the cuticle to constitute a barrier against xenobiotics and pathogens.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"181 ","pages":"Article 104314"},"PeriodicalIF":3.2,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902232","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}

{"title":"The synthesis of nitric oxide regulated by JNK pathway in the pea aphid to defend against bacterial infection","authors":"Li Ma ,&nbsp;Yaya Liu ,&nbsp;Jing Sun ,&nbsp;Xiaorong Yang ,&nbsp;Yingying He ,&nbsp;Tingting Zhang ,&nbsp;Jingyu Zhao ,&nbsp;Zhiqiang Lu ,&nbsp;Xizhong Yan ,&nbsp;Xingtao Qie","doi":"10.1016/j.ibmb.2025.104315","DOIUrl":"10.1016/j.ibmb.2025.104315","url":null,"abstract":"<div><div>Compared to other insects, the pea aphid <em>Acyrthosiphon pisum</em> exhibits limited immune responses, particularly due to the absence of many immune genes, including those encoding antimicrobial peptides and key components of the IMD pathway. Prior studies proved that the conserved signaling, Jun N-terminal kinase (JNK) pathway, plays a critical role in the immune system of the pea aphid, and nitric oxide synthase (NOS) is required for the pea aphid's defense against infections. Herein, using <em>in vitro</em> biochemical assays and <em>in vivo</em> bioassays, we demonstrated that the JNK pathway directly regulates the expression of <em>NOS</em> and that the JNK pathway-NOS-NO signal axis is efficient in defending against bacterial infections. The Toll pathway is instrumental for combating bacterial infections, and NO can activate the Toll pathway. The Toll pathway induced by NO regulates the expressions of ROS metabolism, lysosome, and phagocytosis-related genes. NO was identified as a crucial signaling molecule that facilitates communication between the JNK and Toll pathways.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"180 ","pages":"Article 104315"},"PeriodicalIF":3.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143868438","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}

{"title":"Molecular and pharmacological characterization of the dopamine receptors in the oriental fruit fly, Bactrocera dorsalis","authors":"Shiyan Liu ,&nbsp;Xuefeng Zhang ,&nbsp;Xin Gong ,&nbsp;Jinxin Yu ,&nbsp;Tao Lin ,&nbsp;Qian Xiang ,&nbsp;Xinnian Zeng ,&nbsp;Jiali Liu","doi":"10.1016/j.ibmb.2025.104312","DOIUrl":"10.1016/j.ibmb.2025.104312","url":null,"abstract":"<div><div>Dopamine (DA) is a critical molecule within the insect nervous system, known to regulate a myriad of physiological functions and instigate behavioral shifts in insects. It exerts its effects by interacting with specific dopamine receptors (DARs). In this study, three DARs cDNAs from <em>Bactrocera dorsalis</em> (Hendel) (Diptera: Tephritidae) (<em>BdDOP1</em>, <em>BdDOP2</em> and <em>BdDOP3</em>) were cloned using molecular biology techniques. These receptors exhibited high sequence identity with their orthologous DARs, and phylogenetic analyses also clustered these receptors within their respective receptor subtype. Additionally, the high expression levels of these DARs in the head suggest their prominent role in the central nervous system of <em>B. dorsalis</em>. To investigate the pharmacological properties of these receptors, expression vectors for <em>BdDOP1</em>, <em>BdDOP2</em> and <em>BdDOP3</em> were constructed and expressed in HEK-293T cells. Our results demonstrated that DA and synthetic agonists activated these receptors in a dose-dependent manner, and DA activation can be competitively inhibited by various antagonists, exhibiting distinct potencies for each dopamine receptor type. Among the tested antagonists, SCH-23390, methiothepin, and metoclopramide were identified as the most potent inhibitors of <em>BdDOP1</em>, <em>BdDOP2</em> and <em>BdDOP3</em>, respectively. This study provides valuable insights into the molecular and pharmacological characteristics of DARs in <em>B. dorsalis</em>, offering a theoretical foundation for the development of novel behavioral modulators targeting these receptors. The findings also serve as a reference for the functional analyses of DARs in other insect species.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"180 ","pages":"Article 104312"},"PeriodicalIF":3.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850635","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}

{"title":"The synergism between metabolic and target-site resistance enhances the intensity of resistance to pyrethroids in Spodoptera exigua","authors":"Yayun Zuo ,&nbsp;Yakun Pei ,&nbsp;Yuan Li ,&nbsp;Shuang Wen ,&nbsp;Xuan Ren ,&nbsp;Lin Li ,&nbsp;Yidong Wu ,&nbsp;Zhaonong Hu","doi":"10.1016/j.ibmb.2025.104313","DOIUrl":"10.1016/j.ibmb.2025.104313","url":null,"abstract":"<div><div>The widespread application of insecticides imposes intense selective pressure on pest populations, driving the evolution of high-level resistance and leading to frequent control failures of pest. Insecticide resistance is primarily mediated through two primary mechanisms: target-site insensitivity and enhanced metabolic detoxification. However, the potential interactions and synergistic effects between these mechanisms remain largely unexplored. In this study, we demonstrate a striking cooperative interaction between these two major resistance mechanisms in a field-derived strain of <em>Spodoptera exigua</em> exhibiting extreme resistance (631-fold) to the pyrethroid insecticide lambda-cyhalothrin. Through genetic mapping and linkage analysis, we identified that this resistance phenotype is conferred by the combined effects of overexpression of the P450 <em>CYP9A9</em> (two copies: <em>CYP9A9a</em> and <em>CYP9A9b</em>) and a target-site mutation (L1014F, <em>kdr</em>) in the voltage-gated sodium channel. Using an introgression approach, we generated two near-isogenic strains: WH-kdr, carrying only the target-site resistance allele (6.2-fold resistance), and WH-CYP9A, harboring only the metabolic resistance genes (79-fold resistance), both compared to the susceptible WH-S strain. CRISPR/Cas9-mediated knockout of both <em>CYP9A9</em> copies in the QP19 strain dramatically reduced resistance from 631-fold to 19-fold, while transgenic expression of the <em>CYP9A9a</em> variant (containing three amino acid substitutions) from QP19 strain in <em>Helicoverpa armigera</em> conferred 39-fold resistance to lambda-cyhalothrin. These findings provide compelling evidence that target-site resistance can significantly potentiate metabolic resistance, resulting in substantially higher resistance levels than either mechanism alone in <em>S. exigua</em>. These findings enhance the understanding of higher level resistance mechanisms mediated by interactions between resistance genes and provide theoretical basis for devising management strategies of insecticide resistance.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"180 ","pages":"Article 104313"},"PeriodicalIF":3.2,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843036","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}

{"title":"Calcofluor disrupts binding of Bt toxin Cry1Ac to midgut receptors in Trichoplusia ni","authors":"Rey O. Cotto-Rivera ,&nbsp;Noelia Joya ,&nbsp;Wei Guo ,&nbsp;Patricia Hernández-Martínez ,&nbsp;Juan Ferré ,&nbsp;Ping Wang","doi":"10.1016/j.ibmb.2025.104311","DOIUrl":"10.1016/j.ibmb.2025.104311","url":null,"abstract":"<div><div>The parasporal crystal proteins (Cry proteins) from the soil bacterium <em>Bacillus thuringiensis</em> (Bt) are major insecticidal toxins in formulated Bt sprays and in current transgenic Bt crops widely used in agriculture. To understand the modes of action of Cry proteins and mechanisms of Cry resistance in insects, it is important to understand the specific interaction of Cry proteins with the specific receptors in the insect midgut. Previous studies have found that the fluorescent brightener Calcofluor could significantly reduce the insecticidal activity of Cry1Ac in the cabbage looper, <em>Trichoplusia ni</em>. In this study, the effects of Calcofluor in <em>T. ni</em> larvae on the structure of the midgut, the composition and abundance of midgut brush border membrane proteins, and the binding of midgut brush border membranes with Cry1Ac were examined. Finally, the inhibiting activity of Calcofluor on the binding of Cry1Ac to midgut binding sites was determined. The results from this study indicated that Calcofluor blocks the binding of Cry1Ac to the midgut binding sites by competitively binding the carbohydrate moieties that are involved in the specific binding of Cry1Ac to the midgut, which consequently inhibits the toxicity of Cry1Ac in larvae. Therefore, this study revealed that carbohydrate moieties on insect midgut brush border membranes play crucially important roles in the functional specific binding of Cry1Ac to the midgut receptors in the pathway of toxicity.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"180 ","pages":"Article 104311"},"PeriodicalIF":3.2,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843034","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}