Insect Biochemistry and Molecular Biology最新文献

{"title":"Involvement of salivary Apolipoprotein D, PuApoD311, in gall formation induced by the tephritid stem gall fly, Procecidochares utilis","authors":"Lifang Li ,&nbsp;Jingyi Ning ,&nbsp;Tao Zhu ,&nbsp;Mingxian Lan ,&nbsp;Mehboob Hussain ,&nbsp;Xi Gao ,&nbsp;Jiaying Zhu ,&nbsp;Guoxing Wu","doi":"10.1016/j.ibmb.2025.104442","DOIUrl":"10.1016/j.ibmb.2025.104442","url":null,"abstract":"<div><div>The tephritid stem gall fly, <em>Procecidochares utilis</em> Stone (Diptera: Trypetidae), serves as an effective biocontrol agent against the invasive plant <em>Eupatorium adenophorum</em> (syn. <em>Ageratina adenophorum</em>) by inducing galls through larval saliva secretions, thereby inhibiting the growth of <em>E. adenophorum</em>. Despite this, the genetic basis of gall induction by <em>P. utilis</em> remains unexplored. This study generated a chromosome-level genome of <em>P. utilis</em>, totaling 467.64 Mb with a scaffold N50 of 74.29 Mb, organized into six pseudochromosomes. Comparative genomic analysis revealed a significant expansion of <em>apolipoprotein D</em> (<em>ApoD</em>) genes—a novel finding among gall-forming insects. Salivary gland transcriptomics identified 124 putative secreted proteins, with <em>ApoD</em> expansions exhibiting predominant expression. Among 29 identified <em>ApoD</em> genes in the <em>P. utilis</em> genome, 24 formed a species-specific clade, predominantly expressed in larvae and salivary glands. Notably, 21 of these genes were associated with salivary gland secretion. <em>PuApoD311</em>, uniquely expressed in <em>P. utilis</em> larvae and salivary glands, was successfully recombinantly produced in Sf9 cells using the baculovirus system. Injection of recombinant <em>PuApoD311</em> into <em>E. adenophorum</em> resulted in the formation of “gall-like structures, characterized by analogous lateral root proliferation” structures, and elevated zeatin levels, indicating its pivotal role in gall formation. These findings contribute to our comprehension of salivary gland protein evolution in <em>P. utilis</em> and the molecular mechanisms governing gall induction by this biocontrol agent.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104442"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145480491","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":"Coordinated horizontal transfer of multiple genes assembles a carotenoid biosynthesis pathway in aphids","authors":"Rong Hu ,&nbsp;Jun Wu ,&nbsp;Siying Li ,&nbsp;Peiyu Yang ,&nbsp;Gang Wu ,&nbsp;Changying Niu ,&nbsp;Shuai Zhan ,&nbsp;Yazhou Chen","doi":"10.1016/j.ibmb.2025.104433","DOIUrl":"10.1016/j.ibmb.2025.104433","url":null,"abstract":"<div><div>Horizontal gene transfer (HGT) plays a crucial role in genome evolution, especially when it enables the acquisition and assembly of multi-step biosynthetic pathways. Here, we investigate the evolutionary origins of carotenoid biosynthesis genes in aphids to determine whether multiple functionally related genes were acquired through HGT. We analyzed carotenoid biosynthesis genes in 23 aphid genomes based on homologs in plants, fungi, and bacteria. Phylogenetic analyses revealed that <em>Geranylgeranyl pyrophosphate synthase</em> (<em>GPS</em>), <em>Phytoene synthase</em> (<em>PS</em>), and <em>Carotenoid desaturase</em> (<em>CD</em>) were acquired via HGT from fungi by ancestral insect species, while <em>Carotenoid cleavage oxygenase</em> (<em>CCO</em>) appears to be a native insect gene. Most insect genomes contain two <em>GPS</em> copies, likely resulting from independent HGT events, whereas aphid genomes exhibit extensive duplication of <em>PS</em> and <em>CD</em>, a pattern uncommon in other insects. Expression analyses across aphid species with distinct pigmentation showed that these genes are broadly transcribed with substantial variability in expression levels. In <em>Myzus persicae</em>, comparative expression analysis between red and green clones, as well as a green-red clone with green and red color polymorphism, revealed that <em>PS-4390</em> is a novel candidate for red pigmentation in <em>M. persicae</em>, in addition to <em>CD-4400</em>, a homolog of the <em>tor</em> gene in <em>Acyrthosiphon pisum</em>. These findings provide strong evidence that HGT can introduce multiple functionally related genes into recipient genomes, allowing them to be co-opted into a functional biosynthetic pathway.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104433"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145457032","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":"Heterologous expression of Nilaparvata lugens (Stål) voltage-gated sodium channels in Sf9 cells for electrophysiological and pyrethroid modulation studies","authors":"Piao Zhao ,&nbsp;Zhen Xiao ,&nbsp;Haihao Ma ,&nbsp;Hang Zhu ,&nbsp;Yong Zhou ,&nbsp;Jia Liu ,&nbsp;Xiaomao Zhou ,&nbsp;Zheming Liu","doi":"10.1016/j.ibmb.2025.104430","DOIUrl":"10.1016/j.ibmb.2025.104430","url":null,"abstract":"<div><div>Voltage-gated sodium channels (VGSCs) are essential for neuronal excitability and serve as primary targets of pyrethroid insecticides. Research on insect VGSCs has relied predominantly on the <em>Xenopus laevis</em> oocytes, yet splice variants containing exon <em>b</em> often fail to generate measurable currents, limiting functional and pharmacological characterization. In this study, we cloned two exon <em>b</em>–containing splice variants from the brown planthopper (<em>Nilaparvata lugens)</em>, NlNav7 (harboring exon <em>l</em>) and a previously uncharacterized NlNav25 (harboring exon <em>k</em>), and established an Sf9 insect cell expression system enabling robust functional expression of these challenging variants. NlNav25 exhibited high expression efficiency, reliable gating kinetics, and tetrodotoxin sensitivity even in the absence of NlTipE. Co-expression of NlTipE further increased current amplitude and slightly shifted voltage dependence, indicating a conserved auxiliary role in promoting channel stability and gating modulation. We further evaluated the sensitivity of NlNav7 and NlNav25 to three pyrethroids. Deltamethrin delayed tail currents with comparable efficacy in both variants. In contrast, transfluthrin delayed inactivation and tail currents: at a saturating concentration 50 μM, the I_45ms/I_peak and tail current modification ratios were 103.0 % and 93.2 % for NlNav7, but only 65.5 % and 56.3 % for NlNav25, despite similar apparent EC₅₀. At 100 μM, etofenprox modified NlNav7 tail currents (62.5 %) more effectively than NlNav25 (34.7 %). These finding indicate that exon <em>k</em>/<em>l</em> critically determines the efficacy of transfluthrin and etofenprox, but not deltamethrin. Collectively, this study establishes a high-efficiency Sf9-based heterologous expression system for <em>N. lugens</em> VGSCs, suitable for rapid functional analysis, high-throughput insecticide screening, and provide insights into splice variant-dependent pyrethroid resistance mechanisms.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104430"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145426376","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":"A fructose-sensitive gustatory receptor links nutrient sensing to lipid metabolism in the red imported fire ant","authors":"Huamei Wen ,&nbsp;Xinyue Ma ,&nbsp;Wenjing Zhang ,&nbsp;Lu Wang ,&nbsp;Yanbin Li ,&nbsp;Dan Lv ,&nbsp;Jianghua Sun ,&nbsp;Dingze Mang","doi":"10.1016/j.ibmb.2025.104440","DOIUrl":"10.1016/j.ibmb.2025.104440","url":null,"abstract":"<div><div>Fructose is an important energy source for many insects, yet its perception and physiological roles in the red imported fire ant, <em>Solenopsis invicta</em>, remain unclear. Here, we show that <em>S. invicta</em> workers strongly prefer sucrose and glucose but demonstrate only weak attraction for fructose. Using Ca²⁺ imaging and intracellular Ca²⁺ assays, we identified <em>SinvGr43a</em> as a fructose-responsive gustatory receptor. While its expression is low in the antennae, reverse transcription-quantitative PCR (RT-qPCR) revealed high levels in the brain and gut, suggesting an internal sensing role. RNA interference-mediated knockdown of <em>SinvGr43a</em> led to reduced production and secretion of short neuropeptide F (sNPF) in the gut and insulin-like peptide (ILP) in both the brain and gut. Moreover, this silencing also downregulated key fatty acid metabolic regulators, including sterol regulatory element-binding protein (SREBP) and fatty acid synthase (FAS), in the fat body, resulting in decreased lipid storage. Our findings demonstrate that <em>SinvGr43a</em> functions primarily as an internal fructose sensor, linking nutrient detection with neuropeptide signaling and lipid metabolism to maintain energy homeostasis in <em>S. invicta</em>.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104440"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145476501","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":"Impact of the photoperiod-responsive circadian clock gene period on reproductive diapause in Chrysoperla nipponensis (Okamoto)","authors":"Xue Kong ,&nbsp;Dandan Li ,&nbsp;Minghui Xu ,&nbsp;Shaofeng Zhong ,&nbsp;Shaoye Liu ,&nbsp;Jeremiah Joe Kabissa ,&nbsp;Yongyu Xu ,&nbsp;Zhenzhen Chen","doi":"10.1016/j.ibmb.2025.104444","DOIUrl":"10.1016/j.ibmb.2025.104444","url":null,"abstract":"<div><div>Reproductive diapause in insects is a crucial seasonal adaptation, predominantly regulated by photoperiod, with the circadian clock providing the internal time reference to measure day or night length. Despite its importance, the role of core circadian clock genes in photoperiodic responses and reproductive diapause induction remains poorly understood. The green lacewing, <em>Chrysoperla nipponensis</em>, an important predatory natural enemy, undergoes reproductive diapause under short-day (SD) conditions. This study aimed to investigate the role of circadian clock gene <em>period</em> (<em>per</em>) in photoperiod-mediated diapause of <em>C. nipponensis</em>. Firstly, we identified and molecularly characterized <em>per</em> in <em>C. nipponensis</em>. The encoded PER protein contains conserved domains (PAS, PAC, Period_C) and clusters phylogenetically with neuropteran and coleopteran orthologs. Next, we examined the spatiotemporal expression pattern of <em>per</em>, revealing that its expression was significantly influenced by photoperiod. The daily expression pattern of <em>per</em> indicates that it measures night length. Functional RNAi assays demonstrated that <em>per</em> knockdown under diapause-inducing (short-day) conditions upregulated other core clock genes (<em>timeless1</em>, <em>cycle</em>, <em>clock</em>), abolished diapause phenotypes (ovarian arrest, lipid accumulation), and triggered precocious reproduction. Furthermore, transcriptional analysis revealed that <em>per</em> silencing upregulates the core circadian clock gene <em>cry1</em> as well as 20-hydroxyecdysone (20E) signaling genes, and reprograms lipid synthesis and metabolism genes under short-day conditions in <em>C. nipponensis</em>. Overall, these findings establish <em>per</em> as a critical genetic switch linking circadian timing to diapause induction in <em>C. nipponensis</em>, offering new insights into the molecular mechanisms of circadian regulation in seasonal adaptations of natural enemies, with potential applications in biological control of agricultural pests.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104444"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145487347","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 leucokinin pathway regulates honey bee sugar consumption via Piezo","authors":"Zhenfang Li,&nbsp;Chengfeng Yang,&nbsp;Yashuai Wu,&nbsp;Xinyue Zhang,&nbsp;Xin Zhou,&nbsp;Shiqi Luo","doi":"10.1016/j.ibmb.2025.104448","DOIUrl":"10.1016/j.ibmb.2025.104448","url":null,"abstract":"<div><div>Nectar serves as the primary carbohydrate source for honey bees, sustaining both individual and colony-wide energy demands. Although nectar from bee-pollinated flowers is rich in sucrose, a preferred sugar for honey bees, the neural mechanisms regulating sucrose intake remain poorly understood. Here, we demonstrated that the leucokinin (LK) neuropeptide and its receptor (LKR) suppress sucrose consumption in worker bees of <em>Apis cerana</em>, as shown through LK supplementation and <em>Lkr</em> RNAi. Gene silencing results revealed that this signaling pathway is inhibited by <em>Lkrial</em> (<em>Lkr</em> Intronic Antisense LncRNA), a novel long non-coding RNA (lncRNA) transcribed antisense to the <em>Lkr</em> locus. Furthermore, by using quantitative PCR and RNAi, we showed that <em>Lk/Lkr</em> signaling cascade activates the mechanosensory ion channel <em>Piezo</em>, which acts downstream to suppresses sucrose intake. Collectively, our findings uncover a previously unrecognized regulatory circuit that is essential for the neural control of sucrose consumption and energy acquisition in <em>A. cerana</em>.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104448"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145511432","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":"Field-deployable CRISPR-Dx for BmNPV and Nosema bombycis: DNA-extraction-free one-pot RPA-Cas12a and Cas12a/Cas13a dual-gene assays with handheld devices","authors":"Na Zhang ,&nbsp;Xuemin Zhou ,&nbsp;Xinhao Jiao ,&nbsp;Zi Liang ,&nbsp;Wenwen Jiang ,&nbsp;Shuyi Liu ,&nbsp;Ping Wu","doi":"10.1016/j.ibmb.2025.104449","DOIUrl":"10.1016/j.ibmb.2025.104449","url":null,"abstract":"<div><div>Simple, accurate, sensitive, and rapid pathogen diagnosis is crucial for effective control of silkworm diseases. Although CRISPR-based nucleic acid detection systems show great potential for on-site detection of silkworm pathogens, their practicality is hindered by complex workflows and reagent-storage constraints. To address these limitations and enhance field suitability, we developed a DNA extraction-free one-pot RPA-CRISPR/Cas12a (DEORC) system and a dual-gene assay for detecting <em>Bombyx mori nucleopolyhedrovirus</em> (BmNPV) and <em>Nosema bombycis</em> using a handheld device. The DEORC assay detects BmNPV in hemolymph samples as early as 6 h post-infection (hpi) and <em>N. bombycis</em> at 10³ spores/mL in spore suspensions. The entire process from sampling to visual readout is completed in approximately 70 min without requiring sophisticated equipment. To further enable off-grid deployment, we lyophilized the Cas12a detection reagents using 1 M betaine as a lyoprotectant, which retained measurable activity for at least one month at 4 °C under our test conditions, facilitating short-term refrigerated transport and field storage. Additionally, the dual-gene assay detects 10³ copies/μL of a double-reference plasmid and simultaneously detects both BmNPV and <em>N. bombycis</em> in a single tube from midgut samples at 48 hpi; when combined with extraction-free techniques, it enables simultaneous detection of both pathogens in hemolymph samples at 72 hpi. Collectively, these advancements provide sensitive and portable tools for on-site sericulture disease management, offering faster and more practical workflows than two-step single-gene and traditional approaches.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104449"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145533966","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":"Herbivore-induced plant root volatiles phthalic acid mediate host selection for Holotrichia parallela larva","authors":"Jiarui Tao ,&nbsp;Xiao Wang ,&nbsp;Changhong Xia ,&nbsp;Xingyuan Wang ,&nbsp;Yifan Zhang ,&nbsp;Jianan Liu ,&nbsp;Juhong Zhang ,&nbsp;Jun Wang ,&nbsp;Jinghui Xi ,&nbsp;Shang Wang","doi":"10.1016/j.ibmb.2025.104452","DOIUrl":"10.1016/j.ibmb.2025.104452","url":null,"abstract":"<div><div>The soil-dwelling grubs of <em>Holotrichia parallela</em> inflict substantial damage to the root systems of key cereal crops, including maize and peanuts, thereby posing a serious threat to agricultural productivity. While the olfactory mechanisms through which above-ground insects utilize odorant receptors (ORs) and odorant co-receptors (Orco) to detect plant volatiles for host localization are well established, the role of OR-mediated chemoreception in the host-seeking behaviors of underground pests remains poorly understood. To address this gap, we systematically compared the volatile compounds released by rhizospheric and aerial plant tissues. Through antennal transcriptome analysis and sequence structure prediction, we identified an odorant receptor with biased olfactory expression—<em>HparOR48</em>. Tissue expression analysis revealed that <em>HparOR48</em> is predominantly expressed in the larval antennae across developmental stages. The functional characterization of <em>HparOR48</em> was performed using the <em>Xenopus laevis oocyte</em> expression system, which demonstrated its broad responsiveness to phthalic acid, a root-emitted acidic volatile. Electroantennogram (EAG) assays further confirmed that phthalic acid elicited significant electrophysiological responses in the larval antennae. Moreover, behavioral assays utilizing a four-arm olfactometer indicated that phthalic acid acts as an attractant for the larvae. Our findings provide clear evidence that H. parallela larvae rely on olfactory recognition of rhizosphere-specific acidic volatiles to guide host-seeking behavior, thereby extending our understanding of chemical interactions between soil-dwelling pests and their host plants.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104452"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145577096","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":"Temperature-responsive spatial-temporal regulation underlies phenotypic plasticity of body pigmentation in Eastern honey bee","authors":"Shuai Wang ,&nbsp;Lifei Qiu ,&nbsp;Yashuai Wu ,&nbsp;Zhenfang Li ,&nbsp;Zhengwei Wang ,&nbsp;Zhenhua Chen ,&nbsp;Shanlin Liu ,&nbsp;Xin Zhou","doi":"10.1016/j.ibmb.2025.104454","DOIUrl":"10.1016/j.ibmb.2025.104454","url":null,"abstract":"<div><div>Temperature-induced variation in body coloration is a widespread form of phenotypic plasticity among insects, often mediated by the differential expression of pigmentation-related genes. Despite extensive documentation of this phenomenon, the molecular mechanisms by which environmental cues modulate pigmentation pathways remain largely unresolved. In this study, we investigated seasonal darkness plasticity in <em>Apis cerana</em>, the Eastern honey bee exhibiting a characteristic “yellow-black” abdominal pattern that responds dynamically to ambient temperature. Individuals reared under lower temperature conditions developed a markedly darker phenotype compared to those maintained at higher temperatures, highlighting a temperature-dependent shift in cuticular pigmentation. Exposure to low temperature also resulted in thicker adult cuticles and a concomitant reduction in water loss rate. The co-occurrence of darkened pigmentation and cuticle thickening corresponds with the colder and drier conditions characteristic of winter in the natural habitat of <em>A. cerana</em>. Furthermore<em>,</em> the Hedgehog (Hh) pathway was found to be enriched during early development stages. Notably, its target gene <em>optomotor-blind</em> (<em>omb</em>), a key temperature-sensitive regulator, was upregulated under decreased temperature, establishing the spatial arrangement of the black stripe at the posterior end of each abdominal tergite. Moreover, transcriptional suppression of <em>omb</em> induced upregulation of the pigmentation gene <em>ebony</em>, whose intrinsic thermally responsive expression directly enhances phenotypic plasticity in epidermal pigmentation, serving as a regulatory amplifier for environment-dependent melanin patterning. At the Pb (black eyes with an unpigmented body) in the mid-pupal period, temperature significantly influences 20-hydroxyecdysone (20E) titers. Integrated analyses combining <em>in vivo</em> 20E injection and LC-MS-based hormone quantification revealed that elevated developmental temperature upregulates 20E titers during the temperature-sensitive window, thereby suppressing the expression of pigmentation-related genes. These findings reveal a two-phase mechanism in which spatial patterning and hormonal signaling are temporally decoupled: <em>omb</em> acts early to establish the pigmentation boundary, while 20E acts later to adjust pigment intensity in a temperature-dependent manner. This layered control system allows <em>A. cerana</em> to fine-tune both the position and extent of abdominal pigmentation, providing a flexible strategy for thermal adaptation.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104454"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145652935","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":"Independent evolution of geraniol-8-hydroxylase activity involved in iridoid formation in the Argentine ant (Linepithema humile)","authors":"Maithili Datta ,&nbsp;Katrin Luck ,&nbsp;Song Wu ,&nbsp;Feng Chen ,&nbsp;Yuko E. Ulrich ,&nbsp;Sarah E. O'Connor ,&nbsp;Tobias G. Köllner","doi":"10.1016/j.ibmb.2025.104441","DOIUrl":"10.1016/j.ibmb.2025.104441","url":null,"abstract":"<div><div>Iridoids are bicyclic monoterpenoids that function as defense and signaling compounds in both plants and insects. Although recent research suggested that iridoids evolved independently in these two kingdoms of life, it remained unclear whether independent evolution of iridoid biosynthesis also occurred across different insect lineages. In order to gain insight into the evolution of iridoids in insects, we examined the first committed step of iridoid biosynthesis, the hydroxylation of geraniol to 8-hydroxygeraniol, in the Argentine ant (<em>Linepithema humile</em>) of the order Hymenoptera. This transformation is typically catalyzed by cytochrome P450 monooxygenases in both plants and insects. By integrating transcriptomic and metabolomic analyses across various body parts, we identified candidate P450 genes potentially involved in this reaction. The candidate genes were heterologously expressed in yeast, and enzyme activity was assessed by supplying geraniol to the yeast cultures. One candidate P450 enzyme displayed geraniol 8-hydroxylase (G8H) activity and was designated LhG8H. Phylogenetic analysis showed that LhG8H is evolutionarily distinct from previously characterized G8H enzymes in the pea aphid (<em>Acyrthosiphon pisum</em>) of the order Hemiptera and the mustard leaf beetle (<em>Phaedon cochleariae</em>) of the order Coleoptera. These results support the hypothesis that geraniol 8-hydroxylase activity, a key step in iridoid biosynthesis, evolved independently within the insect orders Hymenoptera, Hemiptera, and Coleoptera.</div></div>","PeriodicalId":330,"journal":{"name":"Insect Biochemistry and Molecular Biology","volume":"186 ","pages":"Article 104441"},"PeriodicalIF":3.7,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145475253","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}