Research Interests

For over 20 years I have dissected how the soil bacterium Agrobacterium tumefaciens can genetically transform plant cells. The insights derived include fundamental discoveries in plant microbe communication, interkingdom conjugal DNA transfer, plant nuclear localization, and type IV bacterial secretion. Understanding this DNA transfer process led to the design of modified versions of Agrobacterium capable of transferring any DNA of interest to plant cells and the ensuing application to basic research and agricultural biotechnology. Two additional topics are under study. Plant cells are encased in cell walls so individual cells to not touch. Plasmodesmata are membrane-lined channels that span plant cell walls, linking the cytoplasm between adjacent cells. Plasmodesmata fluctuate in aperture, impacting general plant development and defense against pathogens. Plant viruses pirate these channels for intercellular spread during infection and are useful molecular probes for plasmodesmata function. I also study the temporal regulation of plasmodesmata in particular cells and tissues during development, thereby exposing networks of intercellular traffic for micro- and macromolecules. Finally, we use molecular, genetic, and cell biological approaches to analyze genes essential for female reproductive development in Arabidopsis.

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Primary Section

Section 25: Plant Biology