{"title":"To each their own: the diversity of primary sex determination signals in insects.","authors":"Filippo Guerra, Eveline C Verhulst","doi":"10.1016/j.cois.2025.101414","DOIUrl":"https://doi.org/10.1016/j.cois.2025.101414","url":null,"abstract":"<p><p>In insects, sex is defined via a cascade of signals constituted by an initial primary signal, an autoregulatory signal and an actuator that causes sexual differentiation. The cascade is conserved at the level of the actuator, Doublesex, whilst primary signals are hypervariable. These primary sex-determination signals evolve and diversify under the pressure of environmental and genomic forces and within the context of the diverse insect sex-determination systems. We report the known primary sex-determination signals and provide an overview of the forces that drive their evolution. We highlight that closely related species can have different primary sex determination signals, yet these are often functionally conserved in either kick-starting (loop starters) or interrupting (loop breakers) the default sex determination cascade.</p>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":" ","pages":"101414"},"PeriodicalIF":5.8,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144717716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Engineering New CRISPR-Mediated Population Control for Tephritid Pests.","authors":"Serafima Davydova, Angela Meccariello","doi":"10.1016/j.cois.2025.101415","DOIUrl":"https://doi.org/10.1016/j.cois.2025.101415","url":null,"abstract":"<p><p>Tephritid fruit flies threaten the agricultural industry with a rising intensity on a worldwide scale. The application of clustered regularly interspaced short palindromic repeats (CRISPR) in insects has resulted in a current boost of CRISPR studies in tephritid pests. One of the primary pathways towards more efficient population management lies in genetic improvements to the Sterile Insect Technique. Herein, we review the pivotal advances in CRISPR application in non-model tephritid fruit flies in recent years. This consists of proof-of-principle studies to optimise CRISPR tools, applications for female elimination and male sterility, and the existing CRISPR-based systems for population control.</p>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":" ","pages":"101415"},"PeriodicalIF":5.8,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144706681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Recent advances on hormones and behavior in vertebrates: inspiration for and from invertebrate science.","authors":"Luke Remage-Healey","doi":"10.1016/j.cois.2025.101409","DOIUrl":"https://doi.org/10.1016/j.cois.2025.101409","url":null,"abstract":"<p><p>This review, as part of an introduction to the special issue, has two goals: First, I consider the inspiration that vertebrate neuroendocrinologists continue to draw from foundational discoveries in invertebrate species for understanding neuro-hormone signaling and action. Second, I lay out select examples of recent advances in understanding hormones and behavior in vertebrates that might provide fodder for new methodological and/or conceptual advances for entomologists and others. Lastly, I provide some examples of recent efforts incorporating computational modeling that can help inspire ways to balance theoretical and empirical approaches to hormone and neuroendocrine science.</p>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":" ","pages":"101409"},"PeriodicalIF":5.8,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144667379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 evolution of queen competitions to boost productivity.","authors":"Patrick Kennedy","doi":"10.1016/j.cois.2025.101413","DOIUrl":"https://doi.org/10.1016/j.cois.2025.101413","url":null,"abstract":"<p><p>Several authors have argued that social insect workers may boost colony productivity by selecting the most fertile, healthy, or vigorous queens from pools of competing candidates. This represents an unusual hypothesis for social evolution: group-members may gain indirect fitness by cultivating within-group direct fitness competition. I review the status of this hypothesis, and highlight key unsolved questions. Recent results from the epiponine wasps of South America underscore the potential for effective comparative analyses. A combination of field experiments, phylogenetics, and game theoretic modelling across diverse social insects is needed to test the plausibility of adaptations fomenting within-group competition to boost productivity.</p>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":" ","pages":"101413"},"PeriodicalIF":5.8,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144658604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laura C Fricke, Matthew D Villalta, Amelia Ri Lindsey
{"title":"Endosymbionts interacting with sex-determining genes and processes.","authors":"Laura C Fricke, Matthew D Villalta, Amelia Ri Lindsey","doi":"10.1016/j.cois.2025.101410","DOIUrl":"https://doi.org/10.1016/j.cois.2025.101410","url":null,"abstract":"<p><p>Insects are rich in reproductive diversity and in maternally inherited symbionts. Maternal inheritance has selected for a suite of microbial mechanisms that enhance host fitness and skew sex-ratios in favor of females. Recently, there has been significant progress in characterizing the genetic and cellular mechanisms that these maternally transmitted symbionts use to manipulate insect sex. Significant advances include the identification of specific microbial effector proteins that lead to male-killing, parthenogenesis, and feminization in a range of model and non-model insects. Many of these effectors target similar host processes such as dosage compensation and the sex determination cascade that leads to sex-specific splicing of genes including transformer and double-sex. The independent origins of these endosymbionts and their induced phenotypes facilitate an enhanced understanding of convergent evolution and offer opportunities to investigate the mechanisms driving insect reproductive diversity.</p>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":" ","pages":"101410"},"PeriodicalIF":5.8,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144636497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Josquin Daron, Alexander Bergman, Louis Lambrechts
{"title":"Dynamics and evolution of transposable elements in mosquito genomes","authors":"Josquin Daron, Alexander Bergman, Louis Lambrechts","doi":"10.1016/j.cois.2025.101406","DOIUrl":"10.1016/j.cois.2025.101406","url":null,"abstract":"<div><div>Decoding mosquito genomes is essential for understanding their role as vectors of human pathogens. Transposable elements (TEs), once considered ‘junk DNA’, are now recognized as key drivers of genomic plasticity and evolution. These mobile DNA fragments are more abundant in culicine than anopheline mosquitoes, influencing their genome size and complexity. TEs may contribute to mosquito adaptation, influencing traits such as insecticide resistance and habitat expansion. Recent advances in long-read sequencing technologies and functional assays are uncovering TE dynamics, but challenges remain in measuring and manipulating their activity, which is critical to demonstrate their phenotypic effects. Further research into the environmental and biological conditions that activate TEs in mosquitoes, as well as the host mechanisms of TE regulation, such as small RNA pathways, will significantly enhance our understanding of mosquito biology.</div></div>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":"71 ","pages":"Article 101406"},"PeriodicalIF":5.8,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144526781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marlène Goubault , Alice Roux , Mathieu Bussy , Elizabeth A Tibbetts
{"title":"Neuroendocrine control of insect aggression: do environmental stressors modulate aggressive behavior?","authors":"Marlène Goubault , Alice Roux , Mathieu Bussy , Elizabeth A Tibbetts","doi":"10.1016/j.cois.2025.101407","DOIUrl":"10.1016/j.cois.2025.101407","url":null,"abstract":"<div><div>Aggressive behavior is crucial for survival and reproductive success across the animal kingdom, enabling individuals to secure resources and protect against natural enemies. Aggressive behavior is also highly plastic, with animals quickly adjusting their aggression level in response to environmental and social context. Neuroendocrine systems govern this regulation. While the neuroendocrine mechanisms of aggression have been extensively studied in vertebrates, they remain underexplored in insects. Recent advances in analytical techniques have provided new opportunities to investigate these mechanisms with greater precision. This research is particularly timely as insects face an increasing number of environmental stressors, including anthropogenic factors, which disrupt their neuroendocrine systems. This review aims to highlight the roles of hormones (juvenile hormone, ecdysteroids) and biogenic amines (dopamine, tyramine, octopamine, serotonin) in regulating insect aggression, emphasizing recent advances. We further discuss how environmental stressors impact neuroendocrine pathways and the resulting implications for aggression, population stability, and ecosystem services.</div></div>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":"71 ","pages":"Article 101407"},"PeriodicalIF":5.8,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144526782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Melissa Kelley , Patrick A Limbach , Joshua B Benoit
{"title":"tRNA expression and modifications as critical components in the biology of blood-feeding arthropods","authors":"Melissa Kelley , Patrick A Limbach , Joshua B Benoit","doi":"10.1016/j.cois.2025.101404","DOIUrl":"10.1016/j.cois.2025.101404","url":null,"abstract":"<div><div>Alterations to the proteome are necessary for physiological processes in blood-feeding arthropods. To account for this, transfer RNA (tRNA) levels and chemical modifications are utilized for protein synthesis. Here, we discuss an overview of tRNA regulation in blood-feeding systems. This topic expands to host–microbial interactions as tRNA modifications require micronutrients acquired from symbionts and diet. Lastly, modifications are likely involved in the molecular dynamics between vectors and pathogens, which may impact transmission to vertebrate hosts. The tRNA levels and their modifications likely play crucial roles in the tripartite interaction between mosquitoes, their microbiome, and transmissable pathogens, providing a novel target to suppress the spread of mosquito-borne diseases.</div></div>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":"71 ","pages":"Article 101404"},"PeriodicalIF":5.8,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144511673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crosstalk between environmental factors and sex determination pathway: insights from lepidopteran insects and cladoceran crustaceans","authors":"Yasuhiko Kato , Hajime Watanabe","doi":"10.1016/j.cois.2025.101403","DOIUrl":"10.1016/j.cois.2025.101403","url":null,"abstract":"<div><div>Insects exhibit a remarkable diversity of sex determination systems. Sex determining mechanisms have been extensively analyzed using the genetic model insects, such as <em>Drosophila melanogaster</em>, revealing that insect sex is determined in a cell-autonomous manner. The sexual identity of each cell is governed by the conserved transcription factor Doublesex, while the regulatory mechanisms controlling its expression are species specific. In contrast, our understanding of how environmental factors modulate the sex determination pathway remains limited. In this review, we summarize recent discoveries on the crosstalk between environmental factors and sex determination pathways in the lepidopteran insects and the cladoceran crustaceans, which are closely related to insects. We discuss how the symbiotic bacterium <em>Wolbachia</em> hijacks the host WZ/ZZ sex determination pathway in the lepidopteran <em>Ostrinia furnacalis</em>. In addition, we highlight how males that are genetically identical to females are produced in response to environmental stimuli in the cladoceran crustacean <em>Daphnia magna</em>. Based on these findings, we explore the evolutionary, ecological, and applied implications of the molecular mechanisms underlying environmentally influenced sex determination.</div></div>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":"71 ","pages":"Article 101403"},"PeriodicalIF":5.8,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144339982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cooperation and conflict in termite societies","authors":"Judith Korb","doi":"10.1016/j.cois.2025.101401","DOIUrl":"10.1016/j.cois.2025.101401","url":null,"abstract":"<div><div>Termites are social cockroaches that evolved eusociality independently from social Hymenoptera (ants, bees, and wasps). Thus, they are diploid organisms, and this has consequences for the occurrence of conflict in termites. Here, I outline the potential for conflict in termites and summarise studies that tested its actual occurrence. In termites, conflicts over the sex ratio, which are typical for haplodiploid social Hymenoptera, are generally absent. All else equal, in monogamous termite colonies, no genetic conflict exists over one’s own reproduction versus helping to raise siblings. Potential for conflict in termites mainly arises due to two main causes: nonmonogamy of colonies and options for colony inheritance by workers. Nonmonogamy occurs when colonies are founded by more than one pair of reproductives (mainly in the species-rich Termitidae with largely sterile workers) or due to fusion of neighbouring colonies (mainly in wood-dwelling termites with totipotent workers). Nonmonogamy of colonies could favour kin-discriminatory behaviour, but, like in social Hymenoptera, evidence for nepotism is rare. Conflict over inheritance of the natal breeding position commonly arises in species with nonsterile workers, which develop into (neotenic) replacement reproductives and inbreed when their king or queen dies. Conflict over inheritance seems to be widespread, yet conflict resolution mechanisms may have evolved, which might include the evolution of worker sterility. Generally, few experimental data exist for termites; more research is required for firm conclusions. Such studies should consider the strong interaction between workers’ reproductive potential (which varies from totipotent to sterile), power to control their own caste fate, and ecology.</div></div>","PeriodicalId":11038,"journal":{"name":"Current opinion in insect science","volume":"71 ","pages":"Article 101401"},"PeriodicalIF":5.8,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144301311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}