A Novel Functional Genomics Platform for Dissecting Maize Kernel Maturation and Protein Quality.

Vitreous (hard) endosperm formation during kernel maturation is essential for most of maize’s uses but usually confers sub-optimal amino acid composition. A novel functional genomics platform is presented that seeks to understand the developmental genetics of vitreous endosperm formation as well as to identify genes within QTLs for modification of the soft endosperm of the high-lysine opaque-2 (o2) mutant to the agronomically viable, hard endosperm Quality Protein Maize (QPM) version. It also investigates the relationship between kernel texture, protein quality and kernel size in a B73 wild type context and investigates the potential to create novel nutritionally enhanced maize lines by prolamin deletion. Using γ-irradiation of a QPM line to generate opaque revertants, we created a population of 300 mutagenized families. We also generated a collection of 1793 mutagenized families in the B73 reference line. An approach that combines genetic mapping with Illumina DNA and RNA sequencing approach is being used to identify causative deletions in candidate mutants. I present characterization of line 107 and 198; increased lysine opaque kernel variants with major reductions in gamma- and alpha-zeins respectively. Ongoing work and plans for the B73 population, are described.