DepartmentCellular and Integrative Physiology
Crystal Archer, Ph.D.
James Stockand, Ph.D.
Dr. Archer’s interest in membrane proteins and ion channels brought her to UT Health San Antonio in 2011, where she applied biochemical chemical analyses and structural biology methods to improve the understanding of the molecular mechanism of a potassium ion channel. She earned her PhD in Biochemistry, in June 2017, and soon afterward, joined Dr. Jim Stockand’s laboratory at UT Health San Antonio as a postdoctoral researcher. Her current focus is to understand the molecular mechanism of how minor plasma membrane phospholipids regulate ENaC (Epithelial Na+ Channel) function. ENaC is an ion channel that is critical for the transport of Na+ and filtered fluid reabsorption through the epithelial lining of many tissues, such as the lungs and kidney. Evidence suggests that, similar other ion channels, the phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2), prevents the decrease of ENaC open probability, and phosphatidylinositol 3,4,5-bisphosphate (PIP3) further enhances the basal levels of ENaC current. However, the details of the structural and molecular mechanism of how these phospholipids affect ENaC function are still unclear. ENaC is a tetrameric protein, comprised of an alpha, beta and gamma subunit. The Stockand Lab used mutagenesis to show that the amino terminus of the beta and gamma subunits contain sites rich in basic residues that may directly bind to these phospholipids. The goal of my research is to determine the sites of the ENaC subunits that bind these phospholipids and elucidate their biochemical affinities, in an effort to gain structural evidence on how these phospholipids influence the gating of ENaC.