Dean Jeffry L, Dobson Stephen L
Department of Entomology; University of Kentucky; Lexington, KY 40546, USA.
J Med Entomol. 2004 Sep;41(5):894-900. doi: 10.1603/0022-2585-41.5.894.
Prior studies have identified a complicated pattern of interspecific hybridization between members of the Aedes (Stegomyia) scutellaris (Walker) mosquito group, which includes medically important vectors of bancroftian filariasis and dengue. Here, we report that two members of the group, Aedes polynesiensis Marks and Aedes riversi Bohart & Ingram, are both infected with intracellular Wolbachia bacteria. Sequencing of the Wolbachia wsp gene demonstrates that the infections differ from each other and from Wolbachia infections previously reported in mosquitoes. Aedes polynesiensis is the first mosquito identified with a wMel Wolbachia type. Intraspecific crosses of infected and aposymbiotic lines generated via antibiotic treatment show that the Wolbachia infections in both species cause high levels of cytoplasmic incompatibility. Interspecific crosses show that the two species are reproductively isolated. However, repeating the interspecific crosses with aposymbiotic mosquito strains demonstrates that the Wolbachia infections play a role in preventing hybrid offspring. We discuss Wolbachia infections in relation to better defining the evolutionary relationships and causes of speciation within the group, understanding the basis for the observed east-to-west gradient in filarial refractoriness, and developing novel genetic control measures.
先前的研究已经确定了斯氏伊蚊（沃克）蚊群成员之间复杂的种间杂交模式，该蚊群包括班氏丝虫病和登革热的重要医学媒介。在此，我们报告该蚊群的两个成员，即波利尼西亚伊蚊马克斯和里弗斯伊蚊博哈特与英格拉姆，均感染了细胞内沃尔巴克氏体细菌。沃尔巴克氏体wsp基因测序表明，这些感染彼此不同，也与先前在蚊子中报道的沃尔巴克氏体感染不同。波利尼西亚伊蚊是首个被鉴定为感染wMel型沃尔巴克氏体的蚊子。通过抗生素处理产生的感染品系和共生缺失品系的种内杂交表明，这两个物种中的沃尔巴克氏体感染均导致高水平的细胞质不亲和。种间杂交表明这两个物种在生殖上是隔离的。然而，用共生缺失的蚊子品系重复种间杂交表明，沃尔巴克氏体感染在阻止杂交后代方面发挥了作用。我们讨论了沃尔巴克氏体感染与更好地定义该蚊群内的进化关系和物种形成原因、理解观察到的丝虫抗性从东到西梯度的基础以及开发新的遗传控制措施之间的关系。
