Genetics of prezygotic reproductive isolation in natural populations of monk

描述(申请人提供)：我们研究的长期目标是了解有性繁殖有机体自然种群中生殖隔离的遗传学和进化：即物种的起源。这项建议主要研究野生猴花两个姊妹种--野猴花和红花猴的合子生殖隔离的遗传学。以前的研究表明，这些物种共域种群之间的生殖隔离几乎完全是由它们不同的传粉者公会的忠诚度所调节的。白头翁由熊蜂授粉，红花由蜂鸟授粉，传粉者的喜好强烈依赖于它们之间的花色差异。本项目的具体目标是：1.制作控制熊蜂授粉的莱维氏黄蜂和蜂鸟授粉的红衣藻花色差异的4个主要数量性状基因座(QTL)的高分辨率遗传和物理图谱。包含这些QTL的物理区域将被测序和注释。目的2.构建和鉴定控制白花和红花间花色差异的4个主效基因座的高分辨近等基因系。HrNIL将接近于单基因替换，并将适合于现场实验。目的3.通过在自然共生区常见的园艺田间试验中直接观察hrNILs，确定4个花色基因座中的每一个所占的总合合子生殖隔离比例，以及它们的组合效应。4个花色基因座(在所有15个可能的组合中)对传粉者偏好的影响将在田间试验中用hrNILs阵列和“祖先”的M.lewisii进行评估。最后一项实验将直接比较大黄蜂和蜂鸟对莱维氏支原体“祖先”表型的偏好，即在莱维氏支原体背景中的一个4位点的hrNIL，以及衍生的红衣藻。所有15个hrNIL组合的授粉者访问表型，结合来自亲本M.lewisii和M.cardinalis的数据，将使我们能够估计所有4个基因座对生殖隔离的个体和综合效应。我们的预期是，绝大多数(&gt；75%)的生殖隔离将仅归因于这4个花色基因座。这些实验将让我们第一次一瞥任何自然系统中前合子生殖隔离的多基因座遗传学。 公共卫生相关性：我们研究的长期目标是了解有性繁殖有机体自然种群中生殖隔离的遗传学和进化：即物种的起源。地球上的所有生物多样性，包括人类的起源，都是物种形成过程的结果。

DESCRIPTION (provided by applicant): The long-term goal of our research is to understand the genetics and evolution of reproductive isolation in natural populations of sexually-reproducing organisms: i.e., the origin of species. This proposal focuses on the genetics of prezygotic reproductive isolation in wild populations of two sister species of monkeyflower, Mimulus lewisii, and M. cardinalis. Previous studies have demonstrated that reproductive isolation between sympatric populations of these species is mediated almost exclusively by the fidelity of their different pollinator guilds. M. lewisii is pollinated by bumblebees, M. cardinalis is pollinated by hummingbirds, and pollinator preference depends strongly on flower color differences between them. The Specific Aims of this project are to: Aim 1. Produce high-resolution genetic and physical maps of the 4 major quantitative trait loci (QTL) controlling differences in flower color between bumblebee-pollinated M. lewisii and hummingbird-pollinated M. cardinalis. Physical regions containing these QTLs will be sequenced an annotated. Aim 2. Construct and characterize high-resolution near-isogenic lines (hrNILs) for each of the 4 major loci controlling differences in flower color between M. lewisii and M. cardinalis. hrNILs will approximate single-gene substitutions, and will be suitable for field experiments. Aim 3. Determine the proportion of the total prezygotic reproductive isolation between M. lewisii and M. cardinalis attributable to each of the 4 flower color loci, and to their combinatorial effects, by direct observation of hrNILs in common garden field experiments in areas of natural sympatry. The effect of each of the 4 flower color loci (in all 15 possible combinations) on pollinator preference will be assessed in field experiments with arrays of hrNILs and the "ancestral" M. lewisii. A final experiment will directly compare the preference of bumblebees and hummingbirds for the "ancestral" M. lewisii phenotype, a 4-locus hrNIL in a M. lewisii background, and the derived M. cardinalis. The pollinator visitation phenotypes of all 15 hrNIL combinations, combined with data from parental M. lewisii and M. cardinalis, will allow us to estimate the individual and aggregate effect of all 4 loci on reproductive isolation. Our expectation is that the vast majority (>75%) of reproductive isolation in sympatry will be attributable to just these 4 flower color loci. These experiments will provide our first glimpse into the multi-locus genetics of prezygotic reproductive isolation in any natural system. PUBLIC HEALTH RELEVANCE: The long-term goal of our research is to understand the genetics and evolution of reproductive isolation in natural populations of sexually reproducing organisms: i.e., the origin of species. All of the biodiversity on Earth, including the origin of humans, is a result of the process of speciation.