COLLABORATIVE RESEARCH: Genetics and Development of Parallel Pollination System Evolution in Penstemon

这个项目考察了进化变化的可预测程度。 特别是，它将测试的假设，不同的物种进化相似的特点，这样做的变化，在相同的基因。 这一假设将检查使用的植物属Penstemon中的物种已经独立地进化了一套类似的花的字符（例如，长，窄的花，增加花蜜生产，延长生殖器官），以响应蜂鸟授粉。 如果这个假设是正确的，那么在不同的蜂鸟授粉物种中，影响特定特征的基因应该位于基因组中的相似位置。 该项目将使用遗传和基因组方法对四种蜂鸟授粉物种和蜜蜂授粉的密切相关物种进行测试。 此外，本研究将确定性状变化的发育基础（例如细胞大小或细胞增殖的变化）。 在检验主要假设的过程中，该项目将对三种盆蕊花属物种的基因组进行测序，并提供遗传图谱。 这些资源将提供给科学界。 该项目将为一名博士后和几名研究生提供分子和基因组技术以及生物信息学和统计分析方面的培训。 最后，本计划将透过实习及与项目的主要研究者及合作主要研究者的独立学习，向本科生介绍进化生物学及基因组学的科学知识，并着重少数族裔学生的参与。（发育与遗传），在授粉综合征中的不同性状类型（数量与质量性状），以及适应蜂鸟授粉的花的不同起源。 在这样做时，它将提供专门设计的第一个广泛的数据，以确定由多个数量性状组成的复杂多性状综合征的平行表型进化在多大程度上是由平行遗传和发育机制进化的。 代表蜜蜂到蜂鸟授粉花综合征的四个独立过渡的五蕊花属物种对将提供本研究的基础。 对于四个物种对中的每一个，将评估导致不同的蜜蜂和蜂鸟适应花形态的发育差异，以确定差异是否反映了平行的发育过程。 对于相同的四个物种对，遗传作图结合基因组测序将被用来评估是否定量花性状基因座确定独立过渡到蜂鸟授粉对应于同源基因组区域含有相同的一组同源候选基因，这表明平行延伸到遗传水平。 由于很少有研究探讨数量性状的遗传平行性，该项目包括开发一种新的“遗传平行性评分”，以量化数量和质量性状的遗传平行性程度。 最后，通过量化来自绘图研究的遗传系的发育参数，该项目将通过确定蜜蜂和蜂鸟适应物种之间的固定遗传差异如何改变有助于不同花卉性状的特定发育过程，将遗传和发育过程联系起来。

This project examines the extent to which evolutionary change is predictable. In particular, it will test the hypothesis that different species that evolve similar characteristics do so by changes in the same genes. This hypothesis will be examined using species in the plant genus Penstemon that have independently evolved a similar suite of floral characters (e.g. long, narrow flowers, increased nectar production, lengthening of the reproductive organs) in response to pollination by hummingbirds. If this hypothesis is true, then in different hummingbird-pollinated species, genes affecting a given character should be located at similar positions in the genome. The project will test this expectation using genetic and genomic approaches applied to four hummingbird-pollinated species and closely related species pollinated by bees. In addition, this research will determine the developmental basis (e.g. changes in cell size or cell proliferation) for the character changes. In examining the main hypothesis, the project will sequence the genomes of three Penstemon species and provide genetic maps. These resources will be made available to the scientific community. The project will provide training for one postdoc and several graduate students in molecular and genomic techniques, as well as in bioinformatics and statistical analysis. Finally, it will introduce undergraduate students to the sciences of evolutionary biology and genomics through internships and independent study with the PI and co-PI of the project, with a focus on minority student participation.This project examines parallelism across different hierarchical levels (developmental vs. genetic), across different trait types within the pollination syndrome (quantitative vs. qualitative traits), and across different origins of flowers adapted to hummingbird pollination. In doing so, it will provide the first extensive data specifically designed to determine the extent to which parallel phenotypic evolution of a complex multi-trait syndrome, comprised of multiple quantitative characters, evolved by parallel genetic and developmental mechanisms. Penstemon species pairs representing four independent transitions from bee to hummingbird pollination floral syndromes will provide the foundation of this research. For each of the four species pairs, the developmental differences that lead to divergent bee and hummingbird-adapted floral morphologies will be assessed to determine whether differences reflect parallel developmental processes. For the same four species pairs, genetic mapping combined with genome sequencing will be used to assess whether quantitative floral trait loci identified in independent transitions to hummingbird pollination correspond to homologous genomic regions containing the same set of homologous candidate genes, suggestive that parallelism extends to the genetic level. As few studies have examined genetic parallelism in quantitative traits, the project includes the development of a novel 'genetic parallelism score' to quantify the degree of genetic parallelism for both quantitative and qualitative traits. Lastly, by quantifying developmental parameters in genetic lines derived from the mapping study, the project will link genetic and developmental processes by determining how fixed genetic differences between bee- and hummingbird-adapted species alter the specific developmental processes that contribute to divergent floral traits.