1. Howard Hughes Medical Institute, University of California Davis, Davis, United States
2. Department of Microbiology & Molecular Genetics, University of California Davis, Davis, United States
3. Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne, United Kingdom
4. Department of Cellular & Molecular Pharmacology, University of California San Francisco, San Francisco, United States
5. Department of Molecular & Cellular Biology, University of California Davis, Davis, United States