1. Department of Biochemistry, University of Washington, Seattle, Washington, USA
2. Institut Pasteur, Unité de Virologie Structurale, Paris, France
3. CNRS UMR 3569 Virologie, Paris, France
4. Department of Biomedical Engineering, Oregon Health and Science University, Portland, Oregon, USA
5. Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
6. Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA