Daniel F. Klessig
The major focus of our research is to understand, at the biochemical, molecular and cellular levels, how plants protect themselves against microbial pathogens. The interaction of tobacco and Arabidopsis with their viral pathogens Tobacco Mosaic Virus (TMV) and Turnip Crinkle Virus (TCV), respectively, are the two principal (but not exclusive) model systems used. Our main goal is to decipher the signal transduction pathway(s) that leads to induction of plant defenses.
During the past two decades we have identified salicylic acid (SA) and nitric oxide (NO) as two important defense signals involved in the activation of defense responses to pathogens. Current studies are directed at defining components in the SA- and NO-mediated signaling pathways and determining their mechanisms of action using a combination of biochemical, pharmacological, molecular and genetic approaches. The TCV-Arabidopsis pathosystem is being utilized to help understand the early, as well as late, steps in activation of defense responses.