1. Department
of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
2. Discovery, Bristol-Myers Squibb Company, Wallingford, Connecticut 06492, United States
3. Department
of Pharmacology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
4. Department
of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, United States