Yinan Wei, associate professor of chemistry at the University of Kentucky, has received an award to study membrane protein oligomerizations in bilayers. This award, supported by the Chemistry of Life Processes Program in the Chemistry Division of the National Science Foundation, investigates protein-protein interactions in the cell membrane that lead to the assembly of functional protein complexes.

Selective-permeable membranes, which define the boundaries of individual cells and cellular organelles, are essential for energy production to sustain life. Membrane proteins are gates on these highly impermeable barriers, allowing selective exchange of substances and signals across the membrane. Understanding of the molecular recognition process leading to membrane protein structures is essential for improved understanding of protein evolution, function and regulation. The aim of this research is to establish a clear picture of the complexation of one model system, a multidrug efflux transporter, AcrB, in living cells and determine its stability in the cell membrane.

In this study, AcrB is used as a model system and its oligomerization in both detergent micelles and lipid bilayers is quantitatively characterized. The kinetic and thermodynamic aspects of the trimer assembly process are monitored in cells and in reconstituted lipid bilayers using an array of assays and methods developed in preliminary studies.

Outcomes from this project bring new insight into the kinetics and thermodynamics of assembly of a multi-span and multi-domain membrane protein trimer. The protocols and parameters developed in the research provide valuable tools and benchmarks for the research community, which lead the way to new initiatives in membrane protein research.

This project also integrates into an outreach program to introduce science and science careers to girls ages 12-18. Wei collaborates with the Hope Hill Youth Service (Mount Sterling, Kentucky), a program for girls who suffer from histories of abuse and neglect and have behavioral and emotional problems requiring extensive treatment and therapy. The goal of these interactions is to broaden the girls’ knowledge of career opportunities.