About the Authors
Department of Microbiology and Immunology, University of California, San Francisco, California, United States of America
Department of Cell and Tissue Biology, University of California, San Francisco, California, United States of America
The authors have declared that no competing interests exist.
VAR, WCS, and CAG conceived and designed the experiments. VAR, WCS, and GN performed the experiments. VAR analyzed the data. VAR and JW contributed reagents/materials/analysis tools. VAR and CAG wrote the paper.