RUI: Mating System Evolution at the Interface of Populations and Species in Linanthus (Polemoniaceae)

拟议的研究继续探索自交不亲和和自交受精的进化。自交不亲和性(SI)是高等植物的一个共同特征，是一种允许植物识别和拒绝自交花粉的遗传机制。在开花植物的进化史上，SI的崩溃导致了自花受精，这是众所周知的。拟议的一系列实验将探索一种新发现的SI的瞬时形式，它可能代表SI崩溃和向自体受精的进化的“快照”。在L.jepsonii，自花受精被阻止了几个小时或几天，之后花变得完全有能力进行自花受精。拟议中的实验将描述这种现象，它的遗传基础，以及它对自交率的影响。分子方法将被用来探索在瞬时SI程度上不同的种群之间的进化关系。这项拟议的研究将有助于提供关于SI的基本知识，这一现象对作物育种具有重要意义。这一机制的遗传学和生理学基础已经得到了相当多的研究，但我们对SI分解的过程知之甚少。该项目旨在培养本科生。这项研究的模块化性质，包括一系列独立的实验，将允许本科生获得一系列方法的经验，包括田野研究、荧光显微镜、授粉实验和分子技术。

The proposed research continues an ongoing exploration of self-incompatibility and the evolution of self-fertilization in Linanthus (Polemoniaceae). Self-incompatibility (SI), a genetic mechanism that allows plants to recognize and reject self-pollen, is a common feature of higher plants. The breakdown of SI, resulting in self-fertilization, is known to have occurred frequently throughout the evolutionary history of flowering plants. The proposed series of experiments will explore a newly discovered transient form of SI that may represent a "snapshot" in the breakdown of SI and evolution toward self-fertilization. In L. jepsonii, self-fertilization is prevented for a few hours or days, after which flowers become fully capable of self-fertilization. The proposed experiments will characterize this phenomenon, its genetic basis, and its effect on the rate of self-fertilization. Molecular methods will be used to explore evolutionary relationships among populations that differ in the extent of transient SI. The proposed research will contribute basic knowledge about SI, a phenomenon that has important implications for crop plant breeding. The genetic and physiological bases of this mechanism have received considerable study, yet we know little about the process by which SI breaks down. The project has been designed to foster training of undergraduate students. The modular nature of the research, comprising a series of discrete experiments, will allow undergraduates gain experience in a range of methodologies, including field studies, fluorescence microscopy, pollination experiments, and molecular techniques