My lab is studying the seed as a model for plant development. The seed is a complex yet elegant structure that is comprised of three major regions, each with a distinct genetic composition. The diploid embryo and triploid endosperm arise from separate fertilization events, and the diploid seed coat is of maternal origin. Each region is partitioned further into subregions that consist of specific tissues and cell types. Seed development is also biphasic, consisting of 1) the morphogenesis phase in which the embryo and endosperm undergo morphogenetic events that are required for the differentiation of the seed subregions and 2) the maturation phase during which storage macromolecules accumulate in the embryo and endosperm to massive amounts, and the embryo becomes tolerant of desiccation. A comprehensive understanding of seed development requires knowledge of the gene regulatory networks that operate temporally and spatially within the seed.
We have used laser-capture microdissection coupled with RNA sequencing experiments to profile mRNA and small RNA populations genome-wide in every organ, tissue, and cell type of soybean seeds throughout development. We have characterized the DNA methylome of soybean seeds at several stages of development. To complement this information, we have also identified the binding sites of specific transcription factors and modified histones that affect the transcriptional activities of genes. Our studies to dissect the gene regulatory networks that operate during seed development will be discussed.