Candidate genes revealed by a genome scan for mosquito resistance to a bacterial insecticide: sequence and gene expression variations.
Candidate genes revealed by a genome scan for mosquito resistance to a bacterial insecticide: sequence and gene expression variations.
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DOI：
10.1186/1471-2164-10-551
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发表时间：
2009-11-21
期刊：
影响因子：
4.4
通讯作者：
Després L
中科院分区：
文献类型：
--
作者：
Bonin A;Paris M;Tetreau G;David JP;Després L
基因组扫描正在成为研究适应和物种形成的遗传基础的一种日益流行的方法，但仅凭其本身，它们通常无法识别特定的基因或突变(s)。这一缺点有望在不久的将来消失，这要感谢目前正在为许多物种开发的丰富的新基因组资源。在这篇文章中，我们通过对埃及伊蚊进行基因组扫描来预测这个令人兴奋的新时代，目的是寻找参与抵抗苏云金芽孢杆菌亚种的候选基因。以色列（Bti）杀虫毒素。利用约500个基于米特的分子标记对1株抗bti和1株敏感bti菌株的基因组进行了调查，并对菌株间遗传分化程度最高的位点进行了测序，并在埃及伊蚊基因组序列上进行了定位。在这些高度分化的标记附近发现了几个良好的bti耐药候选基因。其中两个编码钙粘蛋白和亮氨酸氨基肽酶，进一步在序列和基因表达水平上进行了检查。在抗性菌株中，钙粘蛋白基因显示出与正选择作用一致的核苷酸多态性模式（例如，与中频突变相比，高频率突变过多），以及与敏感菌株相比，显着的低表达。序列和基因表达分析一致表明，抗性菌株中钙粘蛋白基因的进化存在正向选择的作用。然而，对Bti的抗性不太可能仅由该基因赋予，需要进一步研究表征与伊蚊Bti抗性显著相关的其他基因。蚊。除了这些结果之外，本文还说明了基因组扫描如何建立在新的基因组信息（这里是全基因组序列和MITE表征）的基础上，最终实现它们的承诺，并帮助确定适应和物种形成的候选基因。
Genome scans are becoming an increasingly popular approach to study the genetic basis of adaptation and speciation, but on their own, they are often helpless at identifying the specific gene(s) or mutation(s) targeted by selection. This shortcoming is hopefully bound to disappear in the near future, thanks to the wealth of new genomic resources that are currently being developed for many species. In this article, we provide a foretaste of this exciting new era by conducting a genome scan in the mosquito Aedes aegypti with the aim to look for candidate genes involved in resistance to Bacillus thuringiensis subsp. israelensis (Bti) insecticidal toxins. The genome of a Bti-resistant and a Bti-susceptible strains was surveyed using about 500 MITE-based molecular markers, and the loci showing the highest inter-strain genetic differentiation were sequenced and mapped on the Aedes aegypti genome sequence. Several good candidate genes for Bti-resistance were identified in the vicinity of these highly differentiated markers. Two of them, coding for a cadherin and a leucine aminopeptidase, were further examined at the sequence and gene expression levels. In the resistant strain, the cadherin gene displayed patterns of nucleotide polymorphisms consistent with the action of positive selection (e.g. an excess of high compared to intermediate frequency mutations), as well as a significant under-expression compared to the susceptible strain. Both sequence and gene expression analyses agree to suggest a role for positive selection in the evolution of this cadherin gene in the resistant strain. However, it is unlikely that resistance to Bti is conferred by this gene alone, and further investigation will be needed to characterize other genes significantly associated with Bti resistance in Ae. aegypti. Beyond these results, this article illustrates how genome scans can build on the body of new genomic information (here, full genome sequence and MITE characterization) to finally hold their promises and help pinpoint candidate genes for adaptation and speciation.
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影响因子：
9.8
作者：
Akey JM;Eberle MA;Rieder MJ;Carlson CS;Shriver MD;Nickerson DA;Kruglyak L
通讯作者：
Kruglyak L
DOI：
10.1098/rspb.2003.2574
发表时间：
2004-01-07
影响因子：
4.7
作者：
Emelianov, I;Marec, F;Mallet, J
通讯作者：
Mallet, J
影响因子：
--
作者：
Abdullah MA;Valaitis AP;Dean DH
通讯作者：
Dean DH
影响因子：
4.8
作者：
Griffitts, JS;Huffman, DL;Aroian, RV
通讯作者：
Aroian, RV
影响因子：
3.3
作者：
Benjak A;Boué S;Forneck A;Casacuberta JM
通讯作者：
Casacuberta JM