Event
Bioengineering Seminar Series: Sanjay Kumar
Friday, February 27, 2015
9:00 a.m.
Pepco Room (1105), Jeong H. Kim Engineering Building
Assistant Professor Kimberly Stroka
kstroka@umd.edu
Sanjay Kumar
Department of Bioengineering
University of California, Berkeley
Cells and extracellular matrices as smart materials: Dissecting and rebuilding mechaniobiological units
Living cells are capable of processing a variety of mechanical signals encoded within their microenvironment, which can in turn act through the cellular structural machinery to regulate many fundamental behaviors. In this sense, cells may be regarded as "smart materials” that dynamically and locally modulate their physical properties in response to environmental stimuli. Here we discuss our recent efforts to dissect, control, and mimic these phenomena. First, we have used laser nanosurgery to spatially map the nanomechanical properties of actomyosin stress fibers. We have combined this approach with advanced molecular imaging tools (FRAP, FRET) to relate intracellular tensile forces to the conformational activation of mechanosensory proteins at the cell-microenvironment interface and the activities of specific myosin activators and isoforms. Second, we have used the tools of synthetic biology to precisely control the expression and activation of mechanoregulatory proteins in single cells using multiple mutually orthogonal inducer/repressor systems. This capability has enabled us to quantitatively elucidate relationships between signal activation and phenotype and to deconstruct complex signaling networks. By combining these genetic approaches with advanced culture paradigms and in vivo models, we have been able to explore how mechanobiological signals may help drive stem cell differentiation and tumor invasion in the central nervous system. We are now beginning to close the loop by engineering proteins that mimic the stimulus-responsive features of cellular structural networks and may serve as smart, genetically-encoded mechanochemical building blocks.
About the Speaker
Sanjay Kumar, M.D., Ph.D., is Professor of Bioengineering at the University of California, Berkeley, and Chair of the UC Berkeley-UCSF Graduate Program in Bioengineering. Dr. Kumar earned a B.S. in chemical engineering (1996) from the University of Minnesota, where he worked in the laboratory of Matt Tirrell. He then moved on to Johns Hopkins University, where he earned an M.D. (2003) and a Ph.D. in molecular biophysics (2003) as a fellow of the NIH Medical Scientist Training Program. He completed the graduate portion of his training in the laboratories of Jan Hoh of the School of Medicine and Mike Paulaitis of the Department of Chemical Engineering. From 2003-2005, he served as an NIH research fellow with Don Ingber at Children's Hospital Boston and Harvard Medical School. He has been a member of the UC Berkeley faculty since 2005.
Dr. Kumar and his research group have been fortunate to receive a number of honors, including the Presidential Early Career Award for Scientists and Engineers (PECASE), The NIH Director's New Innovator Award, The Arnold and Mabel Beckman Young Investigator Award, the NSF CAREER Award, and the Stem Cells Young Investigator Award. Dr. Kumar has also received awards by student vote for Excellence in Graduate Advising and Outstanding Undergraduate Teaching.
