DISSERTATION RESEARCH: Assessing the Evolutionary Significance of Recurrent Horizontal Gene Transfer of a Chimeric Photoreceptor in Ferns

论文研究：评估蕨类植物嵌合光感受器周期性水平基因转移的进化意义

• 批准号: 1407158
• 负责人: Kathleen Pryer
• 金额: $ 2.04万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1407158&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Assessing; Evolutionary; Significance

This study will provide a deeper understanding of the systematics of ferns and the genes that allow them to grow in shady habitats. The presence of neochrome -- a novel chimeric photoreceptor that fuses red-sensing and blue-sensing photoreceptors into a single gene -- is linked to the ability of ferns to thrive in low-light conditions. Despite its potential importance in adaptation, the evolution of neochrome has remained unexplored. This study will investigate the evolution of neochrome and test the hypothesis that the distribution of the gene is the result of recurrent horizontal gene transfer among ferns. This award will support the research and training of a female doctoral student and undergraduate researchers in diverse molecular and systematic methods. Horizontal gene transfer (HGT) is common in prokaryotes and is often a key driver of adaptation and evolution. However, most documented examples of plant-to-plant HGT involve mitochondrial DNA and/or parasite-host transfers; only a handful of cases include functional nuclear genes, and even fewer have possible adaptive implications. Consequently, plant-to-plant HGT generally has been overlooked as a noteworthy factor in plant evolution. The aim of this research is to use targeted next-generation sequencing of neochrome from diverse fern species to further elucidate the frequency and timing of the seemingly large number of neochrome horizontal gene transfer events in ferns. Because neochrome may have played a major role in promoting the radiation of ferns under low-light environments, this study has important implications for better understanding the evolutionary significance of plant-to-plant HGT.

这项研究将对蕨类植物的系统及其在阴凉的栖息地中生长的基因进行更深入的了解。 Neochrome的存在 - 一种新型的嵌合感光体，将红色 - 感应和蓝色感应光感受器融合到单个基因中 - 与蕨类植物在弱光条件下繁殖的能力有关。尽管在适应中具有潜在的重要性，但新颜料的演变仍未得到探索。这项研究将研究新染料的演变，并检验假设该基因的分布是蕨类植物之间复发水平基因转移的结果。该奖项将支持女性博士生和本科研究人员在各种分子和系统方法方面的研究和培训。水平基因转移（HGT）在原核生物中很常见，通常是适应性和进化的关键驱动力。但是，大多数植物对植物的HGT的例子涉及线粒体DNA和/或寄生虫 - 宿主转移。只有少数病例包括功能性核基因，甚至更少的适应性含义。因此，植物到植物的HGT通常被认为是植物进化中值得注意的因素。这项研究的目的是使用来自不同蕨类物种的Neochrome的有针对性的下一代测序，以进一步阐明蕨类植物中看似大量的新斑点水平基因转移事件的频率和时间。由于新斑点可能在促进弱光环境下蕨类植物的辐射方面发挥了重要作用，因此这项研究对更好地理解植物到植物HGT的进化意义具有重要意义。