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Insecticides, especially pyrethroids, are the most important in the insect pest control and preventing insect vector-borne human diseases. However, insect pests, including mosquitoes, have developed resistance in the insecticides that used against them. Cytochrome P450s are associated with insecticide resistance through overexpression and detoxification mechanisms in insect species. In this study, we utilized a powerful tool, the RNAi technique, to determine the roles of key P450 genes overexpressed in permethrin resistant mosquitoes that confer insecticide resistance to unravel the molecular basis of resistance mechanisms in the mosquito Culex quinquefasciatus. The results showed that knockdown of 8 key P450 genes using RNAi techniques significantly decreased resistance to permethrin in resistant mosquitoes. In silico modeling and docking analysis further revealed the potential metabolic function of overexpressed P450 genes in the development of insecticide resistance in mosquitoes. These findings not only highlighted the functional importance of these P450 genes in insecticide resistance, but also revealed that overexpression of multiple P450 genes was responsible for the high levels of insecticide resistance in a mosquito population of Culex quinquefasciatus .

G-protein-coupled receptors (GPCRs) are known to play central roles in the physiology of many organisms. Members of this seven α-helical transmembrane protein family transduce the extracellular signals and regulate intracellular second messengers through coupling to heterotrimeric G-proteins, adenylate cyclase, cAMPs, and protein kinases. As a result of the critical function of GPCRs in cell physiology and biochemistry, they not only play important roles in cell biology and the medicines used to treat a wide range of human diseases but also in insects’ physiological functions. Recent studies have revealed the expression and function of GPCRs in insecticide resistance, improving our understanding of the molecular complexes governing the development of insecticide resistance. This article focuses on the review of G-protein coupled receptor (GPCR) signaling pathways in insect physiology, including insects’ reproduction, growth and development, stress responses, feeding, behaviors, and other physiological processes. Hormones and polypeptides that are involved in insect GPCR regulatory pathways are reviewed. The review also gives a brief introduction of GPCR pathways in organisms in general. At the end of the review, it provides the recent studies on the function of GPCRs in the development of insecticide resistance, focusing in particular on our current knowledge of the expression and function of GPCRs and their downstream regulation pathways and their roles in insecticide resistance and the regulation of resistance P450 gene expression. The latest insights into the exciting technological advances and new techniques for gene expression and functional characterization of the GPCRs in insects are provided.

Culex mosquitoes are a global vector for multiple human and animal diseases, including West Nile virus, lymphatic filariasis, and avian malaria, posing a constant threat to public health, livestock, companion animals, and endangered birds. While rising insecticide resistance has threatened the control of Culex mosquitoes, advances in CRISPR genome-editing tools have fostered the development of alternative genetic strategies such as gene drive systems to fight disease vectors. However, though gene-drive technology has quickly progressed in other mosquitoes, advances have been lacking in Culex . Here, we develop a Culex- specific Cas9/gRNA expression toolkit and use site-directed homology-based transgenesis to generate and validate a Culex quinquefasciatus Cas9-expressing line. We show that gRNA scaffold variants improve transgenesis efficiency in both Culex quinquefasciatus and Drosophila melanogaster and boost gene-drive performance in the fruit fly. These findings support future technology development to control Culex mosquitoes and provide valuable insight for improving these tools in other species. Culex mosquitoes are a global vector for insect-borne diseases, though progress with genetic tools lags behind other mosquito species. Here the authors present a Cas9-based toolkit and methods that could support future gene drive development in these mosquitoes.

CRISPR-based gene drives can spread through wild populations by biasing their own transmission above the 50% value predicted by Mendelian inheritance. These technologies offer population-engineering solutions for combating vector-borne diseases, managing crop pests, and supporting ecosystem conservation efforts. Current technologies raise safety concerns for unintended gene propagation. Herein, we address such concerns by splitting the drive components, Cas9 and gRNAs, into separate alleles to form a trans-complementing split–gene-drive (tGD) and demonstrate its ability to promote super-Mendelian inheritance of the separate transgenes. This dual-component configuration allows for combinatorial transgene optimization and increases safety by restricting escape concerns to experimentation windows. We employ the tGD and a small–molecule-controlled version to investigate the biology of component inheritance and resistant allele formation, and to study the effects of maternal inheritance and impaired homology on efficiency. Lastly, mathematical modeling of tGD spread within populations reveals potential advantages for improving current gene-drive technologies for field population modification. Gene drives raise safety concerns around unintended propagation. Here the authors present a trans-complementing split-gene drive that requires inheritance of separate transgenes to assemble a fully functional drive.

One method for reducing the impact of vector-borne diseases is through the use of CRISPR-based gene drives, which manipulate insect populations due to their ability to rapidly propagate desired genetic traits into a target population. However, all current gene drives employ a Cas9 nuclease that is constitutively active, impeding our control over their propagation abilities and limiting the generation of alternative gene drive arrangements. Yet, other nucleases such as the temperature sensitive Cas12a have not been explored for gene drive designs in insects. To address this, we herein present a proof-of-concept gene-drive system driven by Cas12a that can be regulated via temperature modulation. Furthermore, we combined Cas9 and Cas12a to build double gene drives capable of simultaneously spreading two independent engineered alleles. The development of Cas12a-mediated gene drives provides an innovative option for designing next-generation vector control strategies to combat disease vectors and agricultural pests. One method for reducing the impact of vector-borne diseases is through the use of CRISPR-based gene drives, which manipulate insect populations due to their ability to rapidly propagate desired genetic traits into a target population. Here the authors describe a Cas12a gene drive system whose activity can be finetuned in a temperature-dependent manner.

The sterile insect technique (SIT) reduces population numbers by releasing sterile males that produce non-viable progeny. Specifically, CRISPR/Cas9-based precision-guided SIT (pgSIT) generates sterile males through genetic crosses of two transgenic lines: a Cas9 strain and a guide RNA (gRNA) strain targeting male sterility and female viability or infertility. However, pgSIT requires separate maintenance of the two lines and sorting to obtain sterile males, creating possible challenges for scaling. To overcome this, we propose using Cas12a nuclease, which is inoperative at lower temperatures but active at higher temperatures. Here, we develop a Cas12a-based pgSIT system involving a single strain containing both the Cas12a nuclease and gRNAs to induce male sterility and female lethality. This strain can be maintained as a mixed stock of both sexes and only activated by increasing temperature, producing sterile males after just one generation. By reducing the challenges that arise with maintaining two separate lines, this system could offer a scalable alternative for vector control in combating vector-borne diseases. Current sterile insect approaches require labor-intensive sorting. Here, authors develop a temperature-controlled Cas12a system in  Drosophila that produces sterile males and eliminates females, offering a scalable genetic tool for controlling pests and disease vectors.

Culex mosquitoes pose a significant public health threat as vectors for a variety of diseases including West Nile virus and lymphatic filariasis, and transmit pathogens threatening livestock, companion animals, and endangered birds. Rampant insecticide resistance makes controlling these mosquitoes challenging and necessitates the development of new control strategies. Gene drive technologies have made significant progress in other mosquito species, although similar advances have been lagging in Culex . Here we test a CRISPR-based homing gene drive for Culex quinquefasciatus , and show that the inheritance of two split-gene-drive transgenes, targeting different loci, are biased in the presence of a Cas9-expressing transgene although with modest efficiencies. Our findings extend the list of disease vectors where engineered homing gene drives have been demonstrated to include Culex alongside Anopheles and Aedes , and pave the way for future development of these technologies to control Culex mosquitoes. Culex mosquitoes are carriers of major diseases like West Nile virus and are a public health concern. Here the authors present a CRISPR-Cas9 gene drive as a control technology in the Culex quinquefasciatus mosquito species.

This study examines whether individuals can effectively express their emotions or “fellow feelings” to a machine, an impartial observer, or individuals who have caused them harm, and the effects of these emotional expressions on behavior. Our findings indicate that the impartial observer is the most preferred outlet for emotional expression, with neither the machine nor the offending party being able to adequately fulfill this role. Negative emotions are more commonly expressed to an impartial observer and a machine, whereas positive emotions are more often directed toward the offending party. Additionally, our findings indicate that emotional expression cannot replace costly punishment and that communication channels do not affect the behavior of the offending party. By exploring the nuanced ways emotions are conveyed, our study offers valuable insights into the evolving discourse on the impact of emotions on human-AI interactions.

This paper reports a study conducted at the whole transcriptome level to characterize the P450 genes involved in the development of pyrethroid resistance, utilizing expression profile analyses of 86 cytochrome P450 genes in house fly strains with different levels of resistance to pyrethroids/permethrin. Interactions among the up-regulated P450 genes and possible regulatory factors in different autosomes were examined in house fly lines with different combinations of autosomes from a resistant house fly strain, ALHF. Eleven P450 genes that were significantly up-regulated, with levels > 2-fold those in the resistant ALHF house flies, were in CYP families 4 and 6 and located on autosomes 1, 3 and 5. The expression of these P450 genes was regulated by trans- and/or cis-acting factors, especially on autosomes 1 and 2. An in vivo functional study indicated that the up-regulated P450 genes also conferred permethrin resistance in Drosophila melanogaster transgenic lines. An in vitro functional study confirmed that the up-regulated P450 genes are able to metabolize not only cis- and trans-permethrin, but also two metabolites of permethrin, PBalc and PBald. In silico homology modeling and the molecular docking methodology further support the metabolic capacity of these P450s for permethrin and substrates. Taken together, the findings of this study highlight the important function of multi-up-regulated P450 genes in the development of insecticide resistance in house flies.

There is an ongoing debate about the type or scale of agriculture that should be most encouraged. This study explores the differences in livelihood levels and outcomes between new agricultural business entities (NABEs) and traditional small households. We applied the analytical tools of a sustainable livelihood framework and a multiple linear regression model to describe the determinants of livelihood outcomes of 105 NABEs and 119 traditional small households in two typical areas around the Sichuan Basin in China. The results show that the overall livelihood level of NABEs is 1.40 times higher than traditional small households. NABEs with a mixed livelihood strategy of both planting and breeding have the highest livelihood level, followed by planting NABEs and breeding NABEs. About 3.13% of all agricultural entities are at risk of falling into poverty; the greater risk levels are associated with the subsidized households (30.00%), pure farmers (12.50%), and part-time farming households (1.69%). NABEs in the study area are verified to use 2.06 times more pesticide and herbicide inputs compared to traditional small households. Education level, technical training, financial accessibility, and the connection with professional cooperatives are common factors influencing the livelihood levels of the two groups of agricultural entities. Livelihood levels of NABEs are also significantly influenced by the age of NABE leaders, planting area per capita, and agricultural insurance. Based on these results, the study proposes policy interventions that are most appropriate for achieving higher livelihood levels among both NABEs and small households. Although the mixed type of NABEs and non-farming households are recognized as being better agricultural entity types for poverty alleviation, we recommend a balance between fostering NABEs and maintaining traditional small households; guidance related to green agriculture production for NABEs is also urgently needed.