1. Department of Pharmacology, University of California at San Diego, La Jolla, CA 92093-0647, USA
2. Medical Scientist Training Program, University of California at San Diego, La Jolla, CA 92093-0647, USA
3. Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093-0647, USA
4. UCSD School of Medicine, University of California at San Diego, La Jolla, CA 92093-0647, USA
5. Howard Hughes Medical Institute, University of California at San Diego, La Jolla, CA 92093-0647, USA
6. Department of Pathology, University of California at San Diego, La Jolla, CA 92093-0647, USA
7. Department of Medicine, University of California at San Diego, La Jolla, CA 92093-0682, USA
8. Division of Otolaryngology-Head and Neck Surgery, University of California at San Diego, La Jolla, CA 92093-0647, USA. Fax: +1 858 534-5270; Tel: +1 858 822-3965