Research Interests

My laboratory has studied several ways in which RNA functions as genetic information and a regulatory molecule. I started my career as a virologist focused on small viruses containing genomes composed of RNA. Using genetic and biochemical approaches, we identified and dissected both plant and viral functions involved in RNA replication, cell-to-cell and long-distance movement, pathogenicity, and defense. By analyzing a protein required for long-distance movement and virulence, we discovered that plant viruses encode suppressors of RNA silencing, or RNA interference. This provided strong evidence for RNA interference functioning as an adaptive defense response in plants. Subsequently, I examined the biological functions, diversification and genomics of RNA silencing, using primarily the model plant Arabidopsis thaliana. We identified several classes of plant small RNA, which all function as molecular guides to confer sequence-specific regulation at the transcriptional and posttranscriptional level. We showed that different types of small RNA, such as short-interfering RNA and microRNA, are formed through the activities of specialized biogenesis components, and provide unique functions through their association with specialized Argonaute proteins. Additionally, we showed how small RNA-directed silencing pathways function across the Arabidopsis genome, which has helped to unravel the ways in which plant genomes are controlled.

Membership Type


Election Year


Primary Section

Section 62: Plant, Soil, and Microbial Sciences

Secondary Section

Section 25: Plant Biology