Ecological Genomics of Anopheles gambiae

描述(申请人提供)：冈比亚按蚊。正在进行的物种形成过程导致疟疾在空间和时间上的传播增加。与物种形成过程相关的生态适应使以前将冈比亚按蚊排除在外的环境得以开发：干旱季节和适合农业灌溉的地区。据推测，适应干旱的初生种(冈比亚按蚊M形)将幼虫的栖息地从S的冈比亚按蚊特有的依赖雨水的池塘和水坑转移到与灌溉有关的人工繁殖地点。然而，M型和S型用来划分不同空间尺度和发展阶段的环境的相关生态特征尚未建立。我们的目标是在表型和基因水平上研究生态适应，因为我们认为这一现象是冈比亚按蚊成为最有效的疟疾媒介的核心，了解它的工作原理将揭示新的控制目标。我们将根据完成的冈比亚按蚊基因组序列和高通量筛选技术，对冈比亚按蚊M和S在不同空间尺度上的生态实地研究进行补充，进行适应的种群基因组检查。为了最终确定复杂生态表型的基因，我们将采用“自上而下”的方法，仔细定义M和S之间的关键生态差异，以及“自下而上”的方法，包括多位点基因组扫描，寻找可能与M和S的生态分化相关的候选区域。在这个框架内，我们提出了以下具体目标：(1)验证M和S划分栖息地的假设，并在不同的空间尺度上描述每种形式实现的生态位；(2)确定M和S内染色体多态与环境异质性的时空格局；以及(3)确定可能与M和S的不同适应相关的基因组区域。

DESCRIPTION (provided by applicant): Anopheles gambiae s.s. is subject to an ongoing speciation process which has resulted in increased malaria transmission spatially and temporally. Ecological adaptation associated with the speciation process has allowed exploitation of environments that formerly excluded A. gambiae: arid seasons and zones subject to irrigation for agriculture. It has been assumed that the arid-adapted incipient species (A. gambiae form M) shifted larval habitats from rain-dependent pools and puddles characteristic of A. gambiae form S to anthropogenic breeding sites associated with irrigation. However, the relevant ecological features used by the M and S forms to partition their environment at different spatial scales and developmental stages have not been established. We aim to study ecological adaptation at phenotypic and genotypic levels because we believe that this phenomenon is central to what makes A. gambiae the most efficient vector of malaria, and that an understanding of how it works will expose novel targets for control. We will complement ecological field studies of A. gambiae M and S at different spatial scales with a population genomic examination of adaptation based on the completed A. gambiae genome sequence and high throughput screening techniques. Toward the ultimate goal of identifying genes underlying complex ecophenotypes, we will apply a "topdown" approach in which key ecological differences between M and S will be carefully defined, and a "bottom-up" approach involving multilocus genome scans for candidate regions likely to be associated with ecological divergence of M and S. Within this framework, we propose the following specific aims: (1) Validate the hypothesis that M and S partition their habitat, and characterize the realized niche of each form at different spatial scales; (2) Define the spatial and temporal patterns of chromosomal polymorphism within M and S in relation to environmental heterogeneities; and (3) Identify genomic regions potentially associated with differential adaptations of M and S.