Laboratoire d'Ecologie Alpine (LECA, UMR 5553 CNRS-Université Grenoble), France.
BMC Genomics. 2010 Mar 31;11:216. doi: 10.1186/1471-2164-11-216.
The control of mosquitoes transmitting infectious diseases relies mainly on the use of chemical insecticides. However, mosquito control programs are now threatened by the emergence of insecticide resistance. Hitherto, most research efforts have been focused on elucidating the molecular basis of inherited resistance. Less attention has been paid to the short-term response of mosquitoes to insecticides and pollutants which could have a significant impact on insecticide efficacy. Here, a combination of LongSAGE and Solexa sequencing was used to perform a deep transcriptome analysis of larvae of the dengue vector Aedes aegypti exposed for 48 h to sub-lethal doses of three chemical insecticides and three anthropogenic pollutants.
Thirty millions 20 bp cDNA tags were sequenced, mapped to the mosquito genome and clustered, representing 6850 known genes and 4868 additional clusters not located within predicted genes. Mosquitoes exposed to insecticides or anthropogenic pollutants showed considerable modifications of their transcriptome. Genes encoding cuticular proteins, transporters, and enzymes involved in the mitochondrial respiratory chain and detoxification processes were particularly affected. Genes and molecular mechanisms potentially involved in xenobiotic response and insecticide tolerance were identified.
The method used in the present study appears as a powerful approach for investigating fine transcriptome variations in genome-sequenced organisms and can provide useful informations for the detection of novel transcripts. At the biological level, despite low concentrations and no apparent phenotypic effects, the significant impact of these xenobiotics on mosquito transcriptomes raise important questions about the 'hidden impact' of anthropogenic pollutants on ecosystems and consequences on vector control.
控制传播传染病的蚊子主要依赖于使用化学杀虫剂。然而，蚊子控制计划现在受到抗药性出现的威胁。迄今为止，大多数研究工作都集中在阐明遗传抗性的分子基础上。对蚊子对杀虫剂和污染物的短期反应的关注较少，而这些反应可能对杀虫剂的功效有重大影响。在这里，使用 LongSAGE 和 Solexa 测序相结合的方法，对登革热媒介埃及伊蚊幼虫进行了深度转录组分析，这些幼虫在 48 小时内暴露于三种化学杀虫剂和三种人为污染物的亚致死剂量下。
测序了 3000 万个 20 bp cDNA 标签，将其映射到蚊子基因组并进行聚类，代表了 6850 个已知基因和 4868 个额外的聚类，这些聚类不在预测基因内。暴露于杀虫剂或人为污染物的蚊子的转录组发生了相当大的改变。编码表皮蛋白、转运蛋白以及参与线粒体呼吸链和解毒过程的酶的基因受到特别影响。确定了可能涉及外来生物反应和杀虫剂耐受性的基因和分子机制。
本研究中使用的方法似乎是研究基因组测序生物中细微转录组变化的有力方法，并可为检测新转录本提供有用信息。在生物学水平上，尽管浓度低且没有明显的表型效应，但这些外来生物对蚊子转录组的显著影响提出了关于人为污染物对生态系统的“隐性影响”以及对病媒控制的后果的重要问题。
