Collaborative Research: RUI: Understanding the effects of ploidal level on responses to global change in plants

当一个生物体的所有染色体都有一个或多个额外的拷贝时，就会发生多倍体或全基因组复制。这种现象在植物中特别常见，最近的估计表明15-30%的植物是多倍体。多倍体物种包括大量具有经济和农业用途的作物和其它植物（例如，棉花、小麦、马铃薯、大豆）。已知多倍体影响植物的广泛的遗传和生理特征，包括与水分利用和光合作用相关的生理性状。多倍体植物可以比二倍体更有活力，具有更广泛的生态位，更广泛的地理分布，并增加入侵新栖息地的能力，所有这些都是由新的遗传组合或基因表达模式驱动的，这些组合或基因表达模式可以在许多性状上产生广泛的变化。该项目将研究多倍体如何影响植物对温度升高和可用水减少的反应能力（即，干旱）。基因表达和生理反应的干旱和温度将测量一组蕨类植物在不同的倍性水平（多倍体量）。了解倍性水平是否以及如何影响美国东部森林的这些重要组成部分，将有助于更好地预测温度和水资源的变化如何影响自然生态系统中的群落结构，并为保护工作提供信息。基因表达变化的信息参与干旱和温度升高的耐受性有可能帮助作物育种计划。该项目的一个组成部分是培养博士后助理，研究生和本科生。该项目的重点是在整个美国东部的森林中发现的一组蕨类植物物种。这是一个自然发生的植物系统，其中多倍体是普遍存在的，其成员在生态系统中具有重要的生态意义。对鳞毛蕨属6种植物的配子体进行了干旱和温度处理的多因子试验。将收集有关生殖和生理生态的数据，以确定温度和水供应的变化如何影响人口统计学和配子体的孢子体招募以及从环境压力中恢复的能力。RNASeq将用于生成基因表达谱，以评估不同温度处理下未应激、脱水和再水化配子体之间的差异。将使用新方法对数据进行分析，以在每细胞、每生物量和每转录组基础上进行差异基因表达分析。结果将在量化实验处理对不同倍性水平的生物体中基因表达的影响方面提供信息，包括在作物植物和非植物系统中。这项工作的结果将提高倍性水平如何影响物种对环境变化的反应的理解。在美国植物学会的年度植物学会议上将举办一个关于如何有效和有益地教授植物生命周期的研讨会，并将使用数据驱动的方法，结合研究结果。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

Polyploidy, or whole genome duplication, occurs when an organism has one or more extra copies of all its chromosomes. This phenomenon is particularly common in plants, and recent estimates suggest that 15-30% of plants are polyploid. Polyploid species include a vast number of crop and other plants with economic and agricultural uses (e.g., cotton, wheat, potato, soybean). Polyploidy is known to influence a wide range of genetic and physiological features of plants, including physiological traits related to water use and photosynthesis. Polyploid plants can be more vigorous than diploids, have broader ecological niches, wider geographic distributions, and increased ability to invade new habitats, all driven by novel genetic combinations or gene expression patterns that can produce extensive changes in many traits. This project will investigate how polyploidy affects plants' ability to respond to increases in temperature and decreases in available water (i.e., drought). Gene expression and physiological responses to drought and temperature will be measured for a set of fern species at different ploidal levels (amounts of polyploidy). Knowing whether and how ploidal level impacts these important components of the eastern forests of the United States will allow better prediction of how changes in temperature and water availability will influence community structure in natural ecosystems and will inform conservation efforts. Information on gene expression changes involved in tolerance of drought and increased temperatures has potential to assist crop breeding programs. An integral part of the project is to train postdoctoral associates, graduate students, and undergraduate students.This project focuses on a set of fern species found in forests throughout the eastern United States. This is a naturally occurring plant system where polyploidy is prevalent, and whose members are ecologically important in the ecosystems where they occur. Gametophytes of six Dryopteris species, including two pairs of a polyploid and its parent taxa, will be grown in a multifactorial experiment with drought and temperature treatments. Data will be collected on reproductive and physiological ecology to determine how changes in temperature and water availability influence demographics and sporophyte recruitment from gametophytes as well as ability to recover from environmental stress. RNASeq will be used to generate gene expression profiles to evaluate differences between unstressed, dehydrated, and rehydrated gametophytes in different temperature treatments. Data will be analyzed using new methods for performing differential gene expression analyses on per-cell, per-biomass, and per-transcriptome bases. Results will be informative in quantifying the effects of experimental treatment on gene expression in organisms at different ploidy levels, including in crop plants and non-plant systems. The results of this work will improve the understanding of how ploidal level may influence species' responses to environmental change. A workshop on how to effectively and engagingly teach plant life cycles will be held at the Botanical Society of America's annual Botany conference, and will use a data-driven approach that incorporates results from the research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.