1. Biochemistry, Cellular and Molecular Biology Program, Johns Hopkins University School of Medicine, 316 Hunterian Building, 725 North Wolfe Street, Baltimore, MD 21205, USA
2. Amgen Scholars Program, Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
3. Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA