1. UCLA/Caltech Medical Scientist Training Program, Los Angeles, California, USA
2. Molecular Biology Institute, University of California, Los Angeles, California, USA
3. Division of Endocrinology, Diabetes, and Metabolism, David Geffen School of Medicine, University of California, Los Angeles, California, USA;
4. Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, California, USA;
5. Department of Pediatrics, David Geffen School of Medicine, University of Los Angeles, California, USA