Intellectual Merit: This project focuses on Pack-MULEs, a special group of "jumping genes" (transposable elements) that are abundant in plants. A unique feature of Pack-MULEs is their ability to duplicate, reorganize, and shuffle DNA fragments in the genome. As a result, Pack-MULEs are potential "gene machines", capable of generating new genes or modifying existing genes and thus contributing to gene and genome evolution. Despite the abundance of Pack-MULEs, little is known about often Pack-MULEs acquire new gene functions or the mechanisms by which these elements duplicate DNA fragments. This research will determine how many of the 3,000 Pack-MULEs in rice encode bona fide proteins and will study the function of a subset of Pack-MULE-associated proteins. In addition, this study will elucidate the impact of Pack-MULE formation on existing genes and determine the factors that promote sequence duplication by Pack-MULEs. Together, these studies will contribute to better understanding of how transposable elements shape genome evolution.
Broader impacts: Students at different levels will be trained with cutting-edge approaches in molecular genetics and computational biology. This project will assist undergraduate students from under-represented groups in their application for graduate study. Through a local public educational garden, this project will provide education to K-12 students and other visitors on the importance of plants for food and on genetic mechanisms that result in phenotypic diversity. The research and education activity involved in this project will raise awareness of the broader public that "genetic engineering" in nature is associated with alternations at both the molecular and phenotypic level.