Elucidating the roles of the beta-2 adrenergic receptor and epidermal growth factor receptor in flavivirus NS1-mediated endothelial dysfunction - PROJECT SUMMARY/ABSTRACT Research Project: Dengue virus (DENV) is a medically important pathogen posing a major public health threat. DENV infection can result in potentially fatal cases of severe dengue associated with vascular leak as a result of endothelial dysfunction, but the triggers of these pathologies were unknown. We and others have defined a direct role for the DENV non-structural protein 1 (NS1) in mediating endothelial dysfunction in vitro and vascular leak in vivo, independently from viral infection, via direct interactions with endothelial cells. Our preliminary data indicate that NS1 binding to endothelial cells and uptake via clathrin-mediated endocytosis are distinct steps that are both critical for NS1-mediated endothelial dysfunction, but the NS1 receptors on endothelial cells that mediate uptake of NS1 are unknown. My preliminary data identified a role for beta-2 adrenergic receptor (β2AR) and epidermal growth factor receptor (EGFR) in NS1-mediated endothelial dysfunction. Further, activation of β2AR has been reported to transactivate EGFR, triggering endocytosis. Thus, I hypothesize that β2AR and EGFR serve as a NS1 receptor complex where NS1 functions as a β2AR agonist to trigger EGFR- mediated endocytosis. This proposal will test this hypothesis by investigating the capacity of NS1 to activate β2AR and EGFR signaling pathways in Aim 1. Aim 2 will investigate the capacity of β2AR and EGFR to serve as NS1 receptors. The proposal holds the potential to characterize a fundamental and novel step in dengue virus pathogenesis via identification of NS1 receptors which also serve as therapeutic targets for treatment of dengue. Candidate and Career Goals: The candidate for this K22 proposal has a strong track record investigating host- pathogen interactions from his work studying entry mechanisms of Nipah virus as an undergraduate student in the labs of Dr. Benhur Lee and Dr. Hector Aguilar-Carreno at the University of California, Los Angeles, investigating innate immune mechanisms by which interferons control viral infection as a graduate student in Dr. Seungmin Hwang’s lab at the University of Chicago, and investigating flavivirus NS1-mediated pathogenesis as a postdoctoral scholar in Dr. Eva Harris’s lab at the University of California, Berkeley. In Dr. Harris’s lab, Dr. Biering recently identified candidate NS1 receptors on endothelial cells and will investigate their role in NS1 pathogenesis in this proposal. Dr. Biering is committed to establishing his own research group at a major research university where he will investigate mechanisms by which viral pathogens cause disease. Career Development Plans and Environment: Dr. Biering will work with his mentor (Dr. Eva Harris) and mentoring committee (Dr. Britt Glaunsinger, Dr. Michael Diamond, Dr. Kamil Godula, Dr. Suzanne Fleiszig, and Dr. P. Robert Beatty) to acquire additional training in biochemistry, advanced-microcopy, glycobiology, and in vivo models of virus infection which will enhance his current research proposal and the research in his future lab. This, coupled with the additional courses and trainings outlined in his training plan, will prepare Dr. Biering for a successful transition to a primary investigator role able to prepare data for a competitive R01 proposal.
