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

合作研究： Penstemon 平行授粉系统进化的遗传学和发展

• 批准号: 1555418
• 负责人: Lena Hileman
• 金额: $ 26.47万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2021-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1555418&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Genetics; Development; Parallel

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.

该项目研究了进化变化的可预测程度。 特别是，它将检验这样一个假设：不同物种通过相同基因的变化进化出相似的特征。 这一假设将使用 Penstemon 植物属中的物种进行检验，这些植物响应蜂鸟授粉而独立进化出一套类似的花特征（例如长而窄的花、花蜜产量增加、生殖器官延长）。 如果这个假设成立，那么在不同的蜂鸟授粉物种中，影响给定特征的基因应该位于基因组中相似的位置。 该项目将使用应用于四种蜂鸟授粉物种和蜜蜂授粉密切相关物种的遗传和基因组方法来测试这一预期。 此外，这项研究还将确定性格变化的发育基础（例如细胞大小或细胞增殖的变化）。 在检验主要假设时，该项目将对三个 Penstemon 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，它将通过实习和与该项目的 PI 和 co-PI 一起进行独立研究，向本科生介绍进化生物学和基因组学科学，重点是少数族裔学生的参与。该项目研究了不同层次级别（发展与发展）之间的并行性。遗传），跨授粉综合症内的不同性状类型（数量与质量性状），以及适应蜂鸟授粉的不同起源的花朵。 在此过程中，它将提供第一个专门设计的广泛数据，以确定复杂多性状综合症的平行表型进化的程度，该综合症由多个数量性状组成，通过平行遗传和发育机制进化。 代表从蜜蜂到蜂鸟授粉花卉综合症的四种独立转变的 Penstemon 物种对将为这项研究奠定基础。 对于四个物种对中的每一对，将评估导致蜜蜂和蜂鸟适应的花形态出现分歧的发育差异，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，遗传作图与基因组测序相结合，将用于评估在蜂鸟授粉的独立过渡中鉴定出的数量花性状位点是否对应于包含同一组同源候选基因的同源基因组区域，这表明平行性扩展到遗传水平。 由于很少有研究检查数量性状的遗传平行性，该项目包括开发一种新颖的“遗传平行性评分”，以量化数量性状和质量性状的遗传平行性程度。 最后，通过量化绘图研究得出的遗传系的发育参数，该项目将通过确定适应蜜蜂和蜂鸟的物种之间的固定遗传差异如何改变导致不同花性状的特定发育过程，将遗传和发育过程联系起来。