MCDB Seminar Series> The Price of Protection: Molecular Control of Plant Growth and Defense

Defense comes at a cost, and in plants that cost can be strikingly visible. Elevated defense is often accompanied by reduced growth, delayed development, and lower seed production. Plants manage this growth–defense balance in part through jasmonate, a lipid-derived hormone produced in response to wounding and insect attack. Jasmonate acts as a molecular glue between an F-box protein and a family of transcriptional repressors, triggering their degradation and thereby activating defense gene expression. I will describe how this signaling mechanism is translated into transcriptional and physiological outputs, and what happens when its components are perturbed. I will show how genetic dissection of this pathway reveals a tight coupling between growth and defense, how the conserved Mediator kinase CDK8 regulates jasmonate-dependent transcription, and how nutrient availability shapes the deployment of particular defense programs. Together, these findings illustrate how plants integrate hormone signaling, transcriptional regulation, and nutrient availability to balance the competing demands of growth and defense.

Bio:
University Distinguished Professor, MSU Foundation Professor, Member, National Academy of Sciences, Fulbright U.S. Scholar

Research: Molecular and Biochemical Basis of Plant-Insect Interactions
Research in our laboratory is aimed at understanding how plants respond to insect herbivory and other forms of wound stress. We use both tomato (Solanum lycopersicum) and Arabidopsis (Arabidopsis thaliana) as experimental model systems for three related areas of investigation: (1) we are elucidating the mechanism of synthesis and action of the plant hormone jasmonate; (2) we are studying how jasmonate-regulated defensive compounds thwart insect attack; and (3) we are studying the development and metabolic function of glandular trichomes in tomato. These projects provide training in several areas of modern plant biology, including: analysis of protein-protein and receptor-hormone interactions; transcriptional networks; plant development; genetics of plant-insect interactions; protein biochemistry/proteomics; metabolism and metabolomics; and crop improvement for insect resistance.