1Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, California, USA
2Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, California, USA
3California Institute for Quantitative Biosciences, University of California, San Francisco, San Francisco, California, USA
4Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, USA
8Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, USA
