Biochemistry - CAFNR
Research at a glance
Area(s) of Expertise
My lab is interested in elucidating novel roles of vesicular trafficking in innate immunity and nutrient-deficiency responses. We focus on host clathrin-coated vesicle (CCV) components with novel roles in innate immune signaling, responses to Pseudomonas syringae pathogenic bacteria and iron (Fe) deficiency responses. This research interest has been ignited by my cross-disciplinary postdoctoral training in protein trafficking in plants (Prof. Natasha Raikhel, DOE Plant Research Lab, Michaigan State University, E. Lansing, MI, USA), sterol requirement in yeast endocytosis (Prof. Howard Riezman, Biozentrum, Basel, Switzerland) and syntaxin phosphorylation in plant immune signaling against pathogenic fungi (Cf-9/Avr9) (Prof. Jonathan Jones, Sainsbury Laboratory, Norwich, England).
The plasma membrane (PM) provides a critical interface between eukaryotic cells and their environment to control cellular responses. In the model plant Arabidopsis, the cellular mechanisms and molecular machineries regulating the PM proteome for effective immune responses and nutrient deficiency responses remain largely elusive. One strategy that cells use to control the protein composition of the PM is trafficking of cargo proteins to and from the PM by vesicular trafficking. Vesicular trafficking is the movement of cargo proteins from one organelle to another in form of small, membrane bound vesicles.
We utilize the plant immune receptor FLAGELLIN SENSING 2 (FLS2) that detects bacterial flagellin or its active peptide-derivative flg22. We and others have shown that FLS2 needs to reside at the PM to perceive flg22 for effective immune responses. A multifaceted vesicle trafficking network is essential for ensuring that FLS2 localizes correctly to its site of function (the PM) and in the correct abundance.
My lab focusses on identifying components of the clathrin-coated vesicle (CCV) network with novel roles in immune signaling and/or trafficking of FLS2 and other proteins with immune functions to and from the cell surface. Our efforts center on CCV components that function in endocytosis and secretion from the PM and the trans-Golgi network, respectively. To address these questions, we use a combination of interdisciplinary techniques including biochemical, cell biological, proteomic, metabolomics, genetic, molecular biological and live-cell imaging approaches. By identifying novel roles for dynamin-related proteins, epsin and clathrin components, our lab has advanced the limited understanding of the identity and role(s) of vesicle components that function in immune responses and/or trafficking of FLS2.
Recently, we have expanded our work from assessing roles of CCV components in flg22-signaling from the model plant Arabidopsis into the field-to-table crop maize. Furthermore, we discovered CCV components that govern Fe-deficiency responses in Arabidopsis, likely by modulating communication between the site at which Fe-deficiency is sensed (leaves) and the site at which Fe is taken up from the soil (root epidermis). We are also deciphering how plants utilize CCV components to help integrate Fe-deficiency and innate immune responses. As a large proportion of the world population rely on plants as their food source for the micronutrient Fe, our long-term goals are to increase yield and nutritional value of crop species to improve food security and human health.
- Ph.D. Botany & Plant Pathology, Michigan State University (PRL)
- M.S. Plant Physiology & Biochemistry, Ruhr Universitat, Bochum, Germany