Cell membranes are interesting from both a physical and biological perspective. On the physical side membranes are two-dimensional fluids capable of occupying three-dimensional space. Their organization is controlled by, and can be therefore be affected by, a number of forces - van der Waals, hydrophobic, hydrogen-bonding, osmotic, screened electrostatic, among others. On the biological side there is increasing evidence that the lipid bilayer, the central structural motif of the membrane, is not merely a passive participant in cell function but rather an active one. The research in the group seeks to bring these two perspectives together to better understand cell function/dysfunction. The students in the group bring a variety of backgrounds, physics, physical chemistry, analytical chemistry and biochemistry – together they tackle this complex and interdisciplinary problem. More specifically, we are interested in the following questions:

Can we control membrane organization and shape with physiological parameters? There is a long, rich history of studying membrane organization. Most of this work however used temperature, which does not fluctuate significantly in living cells, as the control parameter. We have recently identified a system where ionic strength, a parameter that can fluctuate significantly in living systems, can be used to control both the organization and shape of a lipid bilayer.

What happens under non-equilibrium conditions? Much of the research in physics, chemistry and biology occurs under equilibrium conditions. Life, however, occurs under non-equilibrium conditions. With the recent advances in imaging it is possible to easily track membrane components in both space and time. How then, is membrane organization affected by non-equilibrium conditions? Is it significantly different from what is observed under equilibrium conditions?

How do membranes affect the aggregation and toxicity of a-synuclein? Parkinson’s disease is a protein aggregation disease. The protein that aggregates is a-synuclein. Membranes are thought to be involved in both the aggregation of a-synuclein and the toxicity. We are exploring how the protein interacts with membrane and how tuning membrane properties affect aggregation and toxicity. This work is done in collaboration with Professor Chris Rochet in the department of Medicinal Chemistry and Molecular Pharmacology.