BIOPHYSICS SEMINAR<br>Systems Analysis of Clathrin-Coated Pit Dynamics

Clathrin-mediated endoctyosis (CME) maintains cellular and organismal homeostasis by mediating the uptake of essential nutrients, controlling the surface expression of membrane transporters and modulating activity of signaling receptors. A cell not only responds to a myriad of chemical inputs with temporal and spatial precision, but also constantly senses and reacts to its mechanical microenvironment. The fundamental unit of CME is a clathrin-coated pit (CCP) and the dynamic behaviors of individual CCPs have been observed to be highly heterogeneous. To capture and quantify this heterogeneity and use it as a source of mechanistic information, we have combined live cell total internal reflection fluorescence microscopy (TIR-FM) with computational analysis. I will present two aspects of CCP regulation, first on how cortical actin mechanics alters CCP behaviors, and second on how clustering of receptors promotes CCP formation. Understanding these complex interactions leading to CCP formation will be required in order to fully appreciate the role of CME in health and disease. I will also discuss on-going work in the lab on systems and synthetic biology.