Graduate student University of Illinois Urbana-Champaign Urbana, Illinois
Body of Abstract: Bioenergy sorghum is a low-input, drought-resilient, deep-rooting annual crop with high biomass yield potential to enable the sustainable production of biofuels, biopower, and bioproducts. Bioenergy sorghum’s 4-5 m stems account for ~80% of the harvested biomass. Stems accumulate high levels of sucrose that could be used to synthesize bioproducts if information about stem cell-type gene expression and regulation was available to enable engineering. To obtain this information, Laser Capture Microdissection was used to isolate transcriptome profiles from five major cell types present in stems of Sorghum bicolor L. Moench cv. Wray. Transcriptome analysis identified genes with cell-type specific and cell-preferred expression patterns that reflect the distinct characteristics and regulatory functions of each cell type. Analysis of cell-type specific gene regulatory networks (GRNs) revealed that unique TF families contribute to distinct regulatory landscapes, where regulation is organized through various modes and network motifs. Cell-specific transcriptome data was combined with a stem developmental transcriptome dataset to identify the GRN that differentially activates the secondary cell wall formation in stem xylem sclerenchyma and epidermal cells. The cell-type transcriptomic dataset provides a valuable source of information about the function of sorghum stems and GRNs that will enable the engineering of bioenergy sorghum stems.