Genetic specificity and potential for local adaptation between dengue viruses and mosquito vectors
Genetic specificity and potential for local adaptation between dengue viruses and mosquito vectors
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DOI：
10.1186/1471-2148-9-160
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发表时间：
2009-07-09
影响因子：
3.4
通讯作者：
Scott, Thomas W.
中科院分区：
文献类型：
--
作者：
Lambrechts, Louis;Chevillon, Christine;Scott, Thomas W.
背景资料：一些观察结果支持这一假设，即载体驱动的选择在形成登革病毒（DENV）的遗传多样性中起着重要作用。DENV遗传多样性在特定位置的聚集可以反映载体群体的潜在遗传结构，其与特定载体基因型X病毒基因型（G X G）相互作用相结合可以促进病毒谱系对当地蚊子载体基因型的适应。虽然媒介多态性在中性遗传位点的空间结构是有据可查的，蚊子和病毒基因型之间的G × G相互作用的存在还没有正式证明在自然种群。在这里，我们通过用三个同期的DENV-1低传代分离株挑战来自野外埃及伊蚊的三个同雌家族，在代表泰国自然情况的系统中测量G x G相互作用。在所检查的媒介能力指标中，具有中肠感染的蚊子的比例，体内病毒RNA浓度，和传播到头部/腿部的病毒数量（但不是传播性感染的受感染蚊子的比例）强烈依赖于同雌性家族和病毒分离株的特定组合，证明了显著的G x G相互作用。在我们简单的实验设计的相互作用的遗传特异性的证据表明，载体能力的Ae。在遗传多样性的自然群体中，埃及伊蚊对DENV的感染可能在很大程度上受G X G相互作用的控制。这一结果挑战了由蚊子和DENV基因型的单一组合组成的实验室系统的结论的普遍相关性。结合早期的证据，精细尺度的遗传结构的天然AE。埃及种群，我们的发现表明，当地登革病毒适应蚊子载体的必要条件得到满足。
Background: Several observations support the hypothesis that vector-driven selection plays an important role in shaping dengue virus (DENV) genetic diversity. Clustering of DENV genetic diversity at a particular location may reflect underlying genetic structure of vector populations, which combined with specific vector genotype x virus genotype (G x G) interactions may promote adaptation of viral lineages to local mosquito vector genotypes. Although spatial structure of vector polymorphism at neutral genetic loci is well-documented, existence of G x G interactions between mosquito and virus genotypes has not been formally demonstrated in natural populations. Here we measure G x G interactions in a system representative of a natural situation in Thailand by challenging three isofemale families from field-derived Aedes aegypti with three contemporaneous low-passage isolates of DENV-1.Results: Among indices of vector competence examined, the proportion of mosquitoes with a midgut infection, viral RNA concentration in the body, and quantity of virus disseminated to the head/legs (but not the proportion of infected mosquitoes with a disseminated infection) strongly depended on the specific combinations of isofemale families and viral isolates, demonstrating significant G x G interactions.Conclusion: Evidence for genetic specificity of interactions in our simple experimental design indicates that vector competence of Ae. aegypti for DENV is likely governed to a large extent by G x G interactions in genetically diverse, natural populations. This result challenges the general relevance of conclusions from laboratory systems that consist of a single combination of mosquito and DENV genotypes. Combined with earlier evidence for fine-scale genetic structure of natural Ae. aegypti populations, our finding indicates that the necessary conditions for local DENV adaptation to mosquito vectors are met.