1. The Islet Research Laboratory, Whittier Institute for Diabetes, Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, California, USA
2. UCSF Stem Cell Research, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California at San Francisco, San Francisco, California, USA
3. Department of Biochemistry, Christian‐Albrechts‐Universität zu Kiel, Kiel, Germany