2009 DOM Annual Report - Department of Medicine - University of ...

Department of MedicineDr. Bruns, Kleyman and colleagues published a manuscript in J Biol Chem (282:6153-60, 2007) demonstrating that multiple proteases need tocleave the gamma subunit of the epithelial sodium channel (ENaC) to fully activate the channel. Channel activation is due to the release of aninhibitory domain. They proposed that multiple proteolytic cleavage events, including cleavage of the alpha and gamma subunits, lead to astepwise activation of ENaC, reflected in a graded increase in channel open probability.Dr. Weixel, Kleyman and colleagues have a manuscript in press in J Biol Chem that demonstrates regulation of cell surface ENaC expression by anapically localized isoform of phosphatidylinositol 5-kinase (PI5K). Their data suggest that a PI5K-mediated increase in PIP2 levels downregulatesENaC activity via an increase in epsin-dependent endocytosis of the channel.SELECTED SCHOLARLY ACTIVITIESStudy sections (excluding ad hoc review), editorial boards, and other honorsMajor HonorsGerard Apodaca, MERIT Award, National Institutes of HealthLori A. Birder, MERIT Award, National Institutes of HealthThomas R. Kleyman, Recipient of MERIT Award from the NIHGrant ReviewGerard Apodaca, American Heart Association Cell Biology Study Section, ACS Cell Structure and Metastasis Study SectionMary Choi, American Heart Association, National Center, Cardiorenal Study Section, American Society of Nephrology Grant Review54 Better medicine through research and education.