The genetic basis and adaptive significance of divergence in quantitative traits in sympatric Mimulus species

项目摘要 生存和繁殖的变异主要是由于多基因性状的变异。 因此，确定复杂表型中适应性趋异的遗传基础是 不仅在进化生物学中，而且在研究和 治疗人类疾病。很少有研究能够确定单个基因 这是数量性状适应性差异的基础。这项工作的首要目标是 是确定涉及数量性状变异的单个位点，并将这些位点 在自然种群中的适应性。以前的努力之所以失败，要么是因为（1） 数量性状基因座（QTL）定位研究提供了有限的解决方案， 精确定位特定基因，或（2）候选基因和性状的变异对 在自然种群中无法检验适合度。拟议的工作将克服这些问题 限制在两个方面。首先，确定涉及生态相关的个体基因座， 复杂的特征，如物候，交配系统，和形态，我们计划联合收割机 利用全基因组关联研究高世代杂种QTL定位， 群体基因组扫描用于自然群体中的选择。第二，我们将执行 使用基因重组个体进行的相互移植研究， 从数量性状的遗传变异到原生栖息地适合度的变异。米穆卢斯 guttatus species complex是一个理想的系统，在其中研究适应的遗传学， 数量性状，因为它是一种生态多样性，实验上易于处理， 具有许多遗传和基因组工具的野花的互育群。使用此 Mimulus中的方法组合将使我们能够解决以下基本问题 进化问题：空间条件下局部适应的遗传结构是什么？ 和随时间变化的选择复杂性状的进化是否可以预测 分子水平？基因型与环境互作的遗传基础是什么？我们 这项工作使用了一种强大的综合方法来研究复杂性状的进化， 自然人口。数量性状对环境变化的反应 空间对于复杂疾病的演变和农业 重要的植物和动物在不断变化的气候。

PROJECT SUMMARY Variation in survival and reproduction is due largely to variation in polygenic traits. Therefore, identifying the genetic basis of adaptive divergence in complex phenotypes is of paramount importance not only in evolutionary biology, but also in the study and treatment of human disease. Few studies have been able to identify the individual genes that underlie adaptive differences in quantitative traits. The overarching goal of this work is to identify the individual loci involved in quantitative trait variation and link those loci to fitness in natural populations. Previous efforts have fallen short either because (1) quantitative trait locus (QTL) mapping studies provided limited resolution and failed to pinpoint particular genes, or (2) the effects of variation in candidate genes and traits on fitness could not be tested in natural populations. The proposed work will overcome these limitations in two ways. First, to identify individual loci involved in ecologically relevant complex traits such as phenology, mating system, and morphology, we plan to combine QTL mapping in advanced generation hybrids with genome wide association studies and population genomic scans for selection in natural populations. Second, we will perform reciprocal transplant studies using genetically recombinant individuals to causally link genetic variation in quantitative traits to variation in fitness in native habitats. The Mimulus guttatus species complex is an ideal system in which to study the genetics of adaptation in quantitative traits because it is an ecologically diverse, experimentally tractable, and highly inter-fertile group of wildflowers with many genetic and genomic tools. Using this combination of approaches in Mimulus will allow us to address the following fundamental evolutionary questions: What is the genetic architecture of local adaptation under spatially and temporally varying selection? Is evolution in complex traits predictable at the molecular level? What is the genetic basis of genotype by environment interactions? Our work uses a powerful integrative approach to examine the evolution of complex traits in natural populations. How quantitative traits respond to environmental variation in time and space has important implications for the evolution of complex diseases and agriculturally important plants and animals in a changing climate.