Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L35QA, UK.
Present Address: Parasitology Unit, Centre for Infectious Diseases, Universitätsklinikum, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany.
BMC Genomics. 2021 May 10;22(1):337. doi: 10.1186/s12864-021-07646-7.
Malaria control is heavily reliant on the use of insecticides that target and kill the adult female Anopheline vector. The intensive use of insecticides of the pyrethroid class has led to widespread resistance in mosquito populations. The intensity of pyrethroid resistance in some settings in Africa means mosquitoes can contact bednets treated with this insecticide class multiple times with minimal mortality effects. Furthermore, both ageing and diel cycle have been shown to have large impacts on the resistance phenotype. Together, these traits may affect other aspects of vector biology controlling the vectorial capacity or fitness of the mosquito.
Here we show that sublethal exposure of a highly resistant Anopheles coluzzii population originally from Burkina Faso to the pyrethroid deltamethrin results in large and sustained changes to transcript expression. We identify five clear patterns in the data showing changes to transcripts relating to: DNA repair, respiration, translation, behaviour and oxioreductase processes. Further, we highlight differential regulation of transcripts from detoxification families previously linked with insecticide resistance, in addition to clear down-regulation of the oxidative phosphorylation pathway both indicative of changes in metabolism post-exposure. Finally, we show that both ageing and diel cycle have major effects on known insecticide resistance related transcripts.
Sub-lethal pyrethroid exposure, ageing and the diel cycle results in large-scale changes in the transcriptome of the major malaria vector Anopheles coluzzii. Our data strongly supports further phenotypic studies on how transcriptional changes such as reduced expression of the oxidative phosphorylation pathway or pyrethroid induced changes to redox state might impact key mosquito traits, such as vectorial capacity and life history traits.
疟疾控制严重依赖于使用杀虫剂来靶向和杀死成年雌性按蚊传播媒介。拟除虫菊酯类杀虫剂的大量使用导致了蚊子种群的广泛耐药性。在非洲的一些地方，拟除虫菊酯类杀虫剂的耐药性强度意味着蚊子可以多次接触用这种杀虫剂处理过的蚊帐，而不会产生最小的死亡率影响。此外，老化和昼夜节律都被证明对耐药表型有很大的影响。这些特征共同作用可能会影响控制蚊子传播能力或适应度的其他方面的媒介生物学。
在这里，我们展示了来自布基纳法索的高度耐药的按蚊种群在亚致死暴露于拟除虫菊酯类杀虫剂溴氰菊酯后，转录表达发生了显著和持续的变化。我们发现数据中有五种明显的模式，表明与 DNA 修复、呼吸、翻译、行为和氧化还原酶过程相关的转录物发生了变化。此外，我们还突出了与杀虫剂耐药性相关的解毒家族的转录物的差异调节，除了氧化磷酸化途径的明显下调，这都表明暴露后代谢发生了变化。最后，我们表明亚致死拟除虫菊酯暴露、老化和昼夜节律对已知与杀虫剂耐药性相关的转录物有重大影响。
亚致死拟除虫菊酯暴露、老化和昼夜节律导致主要疟疾媒介按蚊的转录组发生大规模变化。我们的数据强烈支持进一步进行表型研究，以了解转录变化（如氧化磷酸化途径表达降低或拟除虫菊酯诱导的氧化还原状态变化）如何影响关键的蚊子特征，如传播能力和生活史特征。
