[1] Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA
[2] Univ Calif San Diego, Sch Med, Biomed Sci Grad Program, San Diego, CA 92093 USA
[3] Univ Calif San Diego, Dept Med, San Diego, CA 92093 USA
[4] Univ Calif San Diego, Sch Med, Dept Pharmacol, La Jolla, CA 92093 USA