Plant seeds are an important part of the human diet, and they also play a vital role in plant reproduction. However, the precise molecular details of how seeds develop and grow are not well understood. The goal of this project is to advance our understanding of seed development, which in turn could have a beneficial outcome for production of seeds as a nutritious food source. The project will also provide interdisciplinary education and training in genetics, genomics, bioinformatics, and molecular biology for high school teachers, undergraduates, graduate students, and postdoctoral fellows. High school science teachers will spend two summers in the laboratory, participating directly in research activities and developing inquiry-based learning modules related to plant biology research, which they will bring back to their classrooms. This partnership will establish long-term connections to teachers to increase their students' ability to analyze quantitative information and generate knowledge from scientific exploration.
Seed development in flowering plants is regulated, in part, by genes that are imprinted. Gene imprinting is an epigenetic phenomenon whereby alleles of genes are differentially expressed depending on whether they are inherited from the male or female parent. To understand and manipulate seed biology to beneficial effect requires deciphering the regulation and function of imprinted gene expression. Recent studies have created catalogues of imprinted genes in diverse plant species, and have yielded important insights about the extent of imprinting and the types of genes subject to imprinted expression. However, it remains unclear whether all imprinting is functional, or whether some instances of imprinting are bystander events due to genome-wide epigenetic reprogramming processes. The major aims of this research project are to comprehensively evaluate the function of imprinted genes in seed development, to test whether pure epigenetic variation is sufficient to induce imprinting variation, and to understand the gene networks that regulate imprinting by taking advantage of natural variation in imprinting phenotypes. This research will have substantial outcomes in further determining the functional consequences of imprinting and in understanding epigenetic mechanisms that regulate imprinted expression, increasing our understanding of seed biology and role of natural variation in these processes. Finally, tools to precisely engineer the DNA methylome in a sequence specific manner will be developed, allowing a direct test of whether specific DNA methylation patterns are necessary and sufficient for imprinted expression. These tools have the potential to be functional in other plant and animal species.
