1. Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095
2. Department of Biological Chemistry, UCLA, Los Angeles, CA 90095
3. HHMI, UCLA, Los Angeles, CA 90095
4. UCLA-Department of Energy Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095
5. Molecular Instrumentation Center, UCLA, Los Angeles, CA 90095
6. VIB-Vrije Universiteit Brussel Center for Structural Biology, VIB and Vrije Universiteit Brussel, Brussels B-1050, Belgium
7. Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095
8. Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095
9. Department of Neurology, University of California San Francisco Weill Institute for Neurosciences, University of California, San Francisco, CA 94143
10. Department of Pathology, University of California, San Francisco, CA 94143
11. Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697