Garegin A. Papoian
Professor
Chemistry & Biochemistry
University of Maryland
Science and Engineering Hall
Time: 2:00pm
800 22nd Street NW, SEH B1220
Washington, DC 20052
Hosted By: Professor Yongsheng Leng ([email protected])
Abstract
Acto-myosin networks are an integral part of the cytoskeleton of eukaryotic cells and play an essential role in determining cellular shape and movement. Acto-myosin network growth and remodeling in vivo is based on a large number of chemical and mechanical processes, which are mutually coupled and spatially and temporally resolved. To investigate the fundamental principles behind the self-organization of these networks, we have developed a detailed physico-chemical, stochastic model of actin filament growth dynamics (MEDYAN), at a single-molecule resolution, where the nonlinear mechanical rigidity of filaments and their corresponding deformations under internally and externally generated forces are taken into account. Our work sheds light on the interplay between the chemical and mechanical processes governing the cytoskeletal dynamics, in particular, the emergence of contractility in these systems, and also highlights the importance of diffusional and active transport phenomena. Our simulations reveal how different acto-myosin micro-architectures emerge in response to varying the network composition.
Biography:
Dr. Papoian received his Ph.D. at Cornell University in 1999, working with Dr. Roald Hoffmann, a Nobel Laureate in Chemistry. He continued with postdoctoral work with Dr. Michael Klein and Dr. Peter Wolynes, studying protein physics. He has held faculty positions first at the University of North Carolina at Chapel Hill, where he was tenured in 2010, moving afterwards to the University of Maryland. He is currently the Monroe Martin Professor of Chemistry and Biochemistry, serving also as the Director of the Chemical Physics Graduate Program at the University of Maryland. Dr. Papoian uses advanced computational methods, based on theoretical physical chemistry, to study biological processes at multiple scales, from single protein functional dynamics and chromatin folding and stability to cell-level processes, such as cell motility.