Helvecio Elisama, Rezende Antonio Mauro, Bezerra Maria J R, de-Melo-Neto Osvaldo Pompílio, de Melo Santos Maria Alice Varjal, Romão Tatiany Patrícia, Ayres Constância Flávia Junqueira
Instituto Aggeu Magalhães-FIOCRUZ, Av. Moraes Rego S/N Cidade Universitária, Recife, PE, 50740-465, Brazil.
Instituto René Rachou-FIOCRUZ, Av. Augusto de Lima, 1715, Barro Preto, Belo Horizonte, MG, 30190-002, Brazil.
Parasit Vectors. 2025 May 14;18(1):174. doi: 10.1186/s13071-025-06675-5.
Resistance to organophosphate compounds is a serious concern in dealing with the control of mosquito vectors. Understanding the genetic and molecular basis of resistance is important not only to create strategies aimed at detecting and monitoring resistance in the field but also to implement efficient control measures and support the development of new insecticides. Despite the extensive literature on insecticide resistance, the molecular basis of metabolic resistance is still poorly understood.
To better understand the mechanisms of Aedes aegypti resistance to temephos, we performed high-throughput sequencing of RNA from the midgut tissue of Aedes aegypti larvae from a temephos-resistant laboratory colony, with long-term and continuous exposure to this insecticide (RecR), as well as from a reference, temephos-susceptible, colony (RecL). Bioinformatic analyses were then performed to assess the biological functions of differentially expressed genes, and the sequencing data were validated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR).
The transcriptome analysis mapped 6.084 genes, of which 202 were considered upregulated in RecR, including known and new genes representing many detoxification enzyme families, such as cytochrome-P450 oxidative enzymes, glutathione-S-transferases and glucosyl transferases. Other upregulated genes were mainly involved in the cuticle, carbohydrates and lipid biosynthesis. For the downregulated profiles, we found 106 downregulated genes in the RecR colony, with molecules involved in protein synthesis, immunity and apoptosis process. Furthermore, we observed an enrichment of KEGG metabolic pathways related to resistance mechanisms. The results found in RT-qPCR confirm the findings of the transcriptome data.
In this study, we investigated transcriptome-level changes maintained in a temephos-resistant Ae. aegypti colony under continuous and prolonged selection pressure. Our results indicate that metabolic resistance might involve a larger and more significant number of detoxification enzymes, with different functional roles, than previously shown with other mechanisms, also contributing to the resistance phenotype in the Ae. aegypti RecR colony.
对有机磷化合物产生抗性是控制蚊媒过程中一个严重的问题。了解抗性的遗传和分子基础不仅对于制定旨在检测和监测田间抗性的策略很重要，而且对于实施有效的控制措施以及支持新型杀虫剂的研发也很重要。尽管有大量关于杀虫剂抗性的文献，但代谢抗性的分子基础仍知之甚少。
为了更好地理解埃及伊蚊对杀螟硫磷的抗性机制，我们对来自长期持续接触该杀虫剂的杀螟硫磷抗性实验室品系（RecR）以及作为对照的杀螟硫磷敏感品系（RecL）的埃及伊蚊幼虫中肠组织的RNA进行了高通量测序。然后进行生物信息学分析以评估差异表达基因的生物学功能，并通过定量逆转录-聚合酶链反应（RT-qPCR）验证测序数据。
转录组分析共定位到6084个基因，其中202个基因在RecR中被认为上调，包括代表许多解毒酶家族的已知和新基因，如细胞色素P450氧化酶、谷胱甘肽-S-转移酶和葡糖基转移酶。其他上调基因主要参与表皮、碳水化合物和脂质生物合成。对于下调的基因谱，我们在RecR品系中发现了106个下调基因，这些分子参与蛋白质合成、免疫和凋亡过程。此外，我们观察到与抗性机制相关的KEGG代谢途径富集。RT-qPCR的结果证实了转录组数据的发现。
在本研究中，我们调查了在持续和长期选择压力下杀螟硫磷抗性埃及伊蚊品系中维持的转录组水平变化。我们的结果表明，与其他机制相比，代谢抗性可能涉及更多具有不同功能作用的解毒酶，这也导致了埃及伊蚊RecR品系的抗性表型。
