Modification of the ABC Program and the Evolution of Floral Novelty.

Elena M.KramerProposal#IOS-0720240 ABC计划的修改和新花的进化进化发展生物学正在解决的一个主要问题是形态创新的遗传基础：新性状是如何产生的？在开花植物中，这可以在新类型的花器官的背景下进行研究。虽然大多数花只表现出萼片、花瓣、雄蕊和心皮，但有些植物产生四种以上的花器官。此外，在进化过程中，出现了许多不寻常的器官细节，这对特定植物群的多样化很重要。该提案支持的工作重点是Aquilegia(科伦拜)，其花表现出三个主要的创新特征：形态独特，艳丽的萼片；具蜜腺的距花瓣；以及存在一种全新的第五种器官类型，称为退化雄蕊，位于雄蕊和心皮之间。分子遗传学方法将被用来特别地消除似乎涉及区分这些新的花器官的基因的功能。此外，基因组技术将有助于识别与花蜜刺突或退化雄蕊等特征发育有关的未知基因。这项研究有可能促进我们对控制花发育的遗传途径的保守以及这些途径随着进化时间的推移而被修改的机制的理解。最终，这里描述的实验将为研究新的花器官识别程序的进化的全球方法奠定基础。将为一名博士后研究员提供培训，并将招募研究生和本科生参与该项目。PI是本科生研究培训计划的积极参与者，并参与了一项针对来自经济困难背景的学业优秀高中生的新计划，这些学生也将有机会参与该项目。

ABSTRACTElena M. KramerProposal #IOS-0720240Modification of the ABC Program and the Evolution of Floral NoveltyOne major question being addressed by evolutionary developmental biology is the genetic basis of morphological innovation: how do new traits arise? In the flowering plants, this can be investigated in the context of new types of floral organs. While most flowers exhibit only sepals, petals, stamens and carpels, some plants produce more than four types of floral organs. Also, over the course of evolution, many unusual organ elaborations have arisen that are important for diversification in specific plant groups. Work supported by this proposal focuses on Aquilegia (columbine) whose flowers exhibit three main innovative features: morphologically distinct, showy sepals; spurred petals with nectaries; and the presence of a completely novel fifth organ type, called staminodia, positioned between the stamens and carpels. Molecular genetic approaches will be used to specifically eliminate the function of genes that appear to be involved in differentiating between these novel floral organs. In addition, genomic techniques will facilitate the identification of unknown genes that are involved in the development of features such as nectar spurs or staminodia. This research has the potential to advance our understanding of both the conservation of the genetic pathways that control floral development and the mechanisms by which these pathways have been modified over evolutionary time. Ultimately, the experiments described here will lay the foundation for a global approach to studying the evolution of novel floral organ identity programs. Training will be provided to a post-doctoral fellow and both graduate and undergraduate students will be recruited to work on the project. The PI is an active participant in undergraduate research training programs and is involved in a new program for academically talented high school students from financially disadvantaged backgrounds, who will also have the opportunity to participate in the project.