1. Duke Molecular Physiology Institute, Duke University, Durham, NC, USA.
2. Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.
3. Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA.
4. Division of Endocrinology, Department of Medicine, Duke University, Durham, NC, USA.
5. Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.