The Valentine Lab at the University of California, Santa Barbara Molecular & Cellular Biomechanics

The Valentine Research Group employs state-of-the-art nanoscale manipulation and measurement techniques to probe diverse biological materials on length scales from that of single proteins (a few nanometers) to that of entire cells (~ 100 microns or more). This highly interdisciplinary work lies at the intersection of engineering, physics, biology and chemistry. Optical microscopy shows structure of reconstituted cytoskeletal networks Megan T. Valentine Assistant Professor Department of Mechanical Engineering Ph.D. Physics, Harvard University M.S. Physics, University of Pennsylvania Burroughs Wellcome Career Award at the Scientific Interface Curriculum vitae

Our primary interest lies in understanding the mechanical properties of the cytoskeleton, a dynamic protein polymer network that forms the foundation of cellular architecture, giving cells strength and enabling them to crawl, change shape and divide. This complex network is comprised of several classes of protein filaments, including actin and microtubules, and is constantly being remodeled through the work of accessory binding proteins that promote changes in filament length and organization. We are particularly interested in the role of motor proteins, enzymes that use the energy released in chemical reactions to exert forces and move in cells.

To investigate the biophysical and biochemical basis of cellular mechanics, we use a wide variety of experimental techniques, including: high-precision optical trapping to probe single molecules of motor and crosslinking proteins; micromechanical manipulation of cytoskeletal networks that are reconstituted from purified components or assembled in cell extracts; and advanced fluorescence imaging of the self-assembly of large protein complexes. We are also working to develop novel methods of measuring interaction and deformation forces within living cells.