About the Authors
Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California, United States of America
Department of Structural Biology, Stanford University School of Medicine, Stanford, California, United States of America
The authors have declared that no competing interests exist.
Conceived and designed the experiments: YZ BKK. Performed the experiments: YZ. Analyzed the data: YZ WIW BKK. Contributed reagents/materials/analysis tools: YZ BKK. Wrote the paper: YZ BKK.