Title: Assessing The Effects of Protein Load on Protein Function

Abstract: Cells exist in a complex mechanical environment that is a source of applied forces and a means of mechanical support. Cells respond to these mechanical signals through a poorly understood process called mechanotransduction. A clearer understanding of this process will lead to improved methods for manipulating cell behavior in engineered tissues and increased understanding of mechanosensitive disease states, such as atherosclerosis and cancer. As mechanotransduction is likely due to force-induced conformation changes in load-bearing proteins, we develop and use protein-based biosensors that exhibit force-dependent changes in the color of emitted light. This technology enables dynamic measurements of mechanical forces at the molecular level that are innately compatible with concepts and approaches common in molecular biology and biophysics, uniquely enabling mechanistic studies of mechanotransduction. The current challenge is developing approaches that reveal the effects of mechanical loading on protein function in living cells. In this talk, I will discuss our efforts to develop new assays for determining whether load-bearing proteins are subject to controlled forces or extensions, probing the relationship between protein load and the composition of key sub-cellular structures, as well as the relationship between protein loading and protein dynamics. I will conclude with a discussion of how these techniques are changing our understanding of the mechanisms cells use to detect and respond to mechanical cues.