1. Department of Chemistry, University of California, Berkeley, California 94720, United States
2. Department of Nutritional Sciences & Toxicology, University of California, Berkeley, California 94720, United States
3. Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, United States
4. Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720, United States
5. Howard Hughes Medical Institute, University of California, Berkeley, California 94720, United States