In my laboratory, we use molecular and biochemical approaches to study the structure, function, regulation and expression of plant genes.
Plants respond to pathogen attack by bacteria, fungi or viruses by synthesizing sets of proteins such as chitinases and glucanases that degrade the cell walls of the invading organism. We are interested in identifying and characterizing the pathogenesis response proteins in cotton that have enhanced resistance to bacterial or fungal infection.
Plant seeds contain large amount of proteins. These seed storage proteins are degraded when the seeds germinate and serve as stores of amino acids and nitrogen for the synthesis of new compounds. These proteins are important for a number of reasons. First, these proteins are the major source of dietary protein that we derive from seed based foods such as peas and beans. Much effort has been applied to developing plants with nutritionally complete seed storage proteins. We are interested in studying the seed storage proteins of wild legume species to determine whether there are plants naturally having a more balanced amino acid composition. We are also studying how seed storage protein composition is influenced by the physiology and natural history of different species.
In conjunction with our studies of the composition of seed storage proteins from wild plants, we are also interested in determining how these proteins evolved. Surprisingly, there is a structural component in seed storage proteins (a beta-barrel motif) that is a member of the cupin superfamily. This superfamily encompasses molecules from a wide variety of species. These studies involve determination of wild vicilin sequences and using phylogenetic analysis and bioinformatic tools to determine evolutionary, structural and functional relationships.
In contrast to orthodox seeds, recalcitrant seeds cannot survive storage conditions like drying and freezing for long periods of time. Zizania aquatica (wild rice) is an annual grass whose grains are harvested as food throughout the world. Our interest focuses on why these seeds cannot survive drying.
Lytic peptides are notorious for their ability to destroy membrane bilayers by causing pore formation or disruption. In an effort to exploit this ability, Nicotiana tabacum tissue was plastid transformed to express a synthetic lytic peptide, D4E1. Our interest are utilizing transformed tissue to determine the peptides ability to bind to membranes, localization during several stages of plant development, and quantify the effects of the peptide on antimicrobial.