Ahsan Ausaf Ali Receives Paul Hatheway Terry Scholarship

graduate student Ahsan Ali

Ahsan Ausaf Ali (You Group) received the Paul Hatheway Terry Scholarship in recognition of excellence in research. Research: The cell membrane is a very important component of cells which plays a critical role in cell signaling and cell-cell communication. Since the cell membrane is fluidic in nature, molecules in it such as lipids and proteins are generally free to associate and dissociate resulting in short lived dynamic interactions. Such short-lived interactions are important because they allow the membrane to modulate the formation signaling platforms in response to specific stimuli. Unfortunately, visualizing these transient interactions has proved to be challenging due to their fast nature and the complex heterogenous composition of membranes. In my research, we use short DNA tags to label certain lipids on the cell membrane which allows us to stabilize these short-lived interactions for long enough so that they may be imaged and quantified. This was achieved by developing a “DNA Zipper” probe where DNA hybridization between different lipid-DNA conjugates may “zip” two transiently interacting probes together to various degrees depending on the DNA sequence chosen. From our experiments we were able to visualize various lipid-lipid interactions and observe their relative strength. We further used our DNA Zipper probe to investigate and visualize the heterogeneity of the cell membrane and its role in several important biological processes including immune cell activation and the progression of cancer. Our current goal is to apply our DNA Zipper to membrane proteins as an approach to quantify transient protein interactions and screen various small molecules which may impact these interactions.