Cholesterol Flip-Flop Dynamics and Nanomechanical Response of Deformed Biomembranes: Experiments and Petascale Simulations

University Of Southern California, Los Angeles CA

Investigators

Abstract

The research objective of this award is to combine experiment and computer simulation to investigate the relationships between cell membrane composition, organization, and mechanical behavior. The nanoscale response of cell membranes to mechanical stress is an essential aspect of important biophysical processes such as endo- and exocytosis, viral fusion and budding, and intracellular trafficking. The joint experimental-simulation studies conducted under this award will probe how molecular processes such as phase separation into liquid-ordered and liquid-disordered domains by membrane lipids and cholesterol flip-flop across the cell membrane bilayer modulate the nanomechanical response of membranes. Newly developed computational tools include a petascale computational framework to perform multimillion-atom MD simulations embedded in coarse-grained MD simulations. These studies will add significantly to biophysical understanding of bending mechanics of cell membranes, which has profound implications for viral infection and neuron communication. The educational plan focuses on a dual-degree program in which students fulfill Ph.D. requirements within their own discipline while studying towards an M.S. in computer science. Dual-degree students will help organize computational science workshops for underrepresented groups, which are held regularly at the University of Southern California. The educational outreach plan also integrates high-school students into experimental research.