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

项目总结 生存和繁殖的差异在很大程度上是由于多基因性状的差异。 因此，确定复杂表型适应性差异的遗传基础是 不仅在进化生物学中，而且在研究和 人类疾病的治疗。很少有研究能够识别出单个基因 这是数量性状适应性差异的基础。这项工作的首要目标是 是识别与数量性状变异有关的单个基因座并将这些基因座联系起来 自然种群的健康状况。之前的努力都失败了，因为(1) 数量性状基因座(QTL)定位研究提供的分辨率有限，未能 精确定位特定基因，或(2)候选基因和性状的变异对 健康状况不能在自然种群中进行测试。拟议的工作将克服这些问题 有两个方面的限制。第一，确定与生态相关的单个基因座 复杂的特征，如物候，交配系统和形态，我们计划结合 利用全基因组关联研究和分子标记定位高世代杂交种的QTL 在自然种群中进行选择的种群基因组扫描。第二，我们将表演 利用基因重组个体进行因果关联的相互移植研究 数量性状的遗传变异与原生生境中适合度的变异。米穆卢斯 点滴状物种复合体是研究适应遗传学的理想系统 数量性状，因为它在生态上是多样的，在实验上容易驯化，并且高度 野花的中间可育群体，有许多遗传和基因组工具。使用这个 Mimulus中的方法组合将使我们能够解决以下基本问题 进化论问题：空间环境下局部适应的遗传结构是什么 以及随时间变化的选择？复杂性状的进化是可以预测的吗 分子水平？基因与环境相互作用的遗传基础是什么？我们的 Work使用一种强大的综合方法来研究人类复杂性状的进化 自然种群。数量性状如何在时间和时间上对环境变化做出反应 空间对复杂疾病的进化和农业具有重要意义 气候变化中的重要动植物。

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.