About the Authors

Kayoko Waki

Affiliation Virus-Cell Interaction Section, HIV Drug Resistance Program, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America

Stewart R. Durell

Affiliation Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America

Ferri Soheilian

Affiliation Electron Microscope Laboratory, Advanced Technology Program, SAIC-Frederick, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America

Kunio Nagashima

Affiliation Electron Microscope Laboratory, Advanced Technology Program, SAIC-Frederick, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America

Scott L. Butler

Current address: Infection Innovative Medicine, AstraZeneca Pharmaceuticals, Waltham, Massachusetts, United States of America

Affiliation Antiviral Biology, Pfizer Global Research & Development, Sandwich Laboratories, Sandwich, Kent, United Kingdom

Eric O. Freed

efreed@nih.gov

Affiliation Virus-Cell Interaction Section, HIV Drug Resistance Program, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America

Competing Interests

I have read the journal's policy and have the following conflicts: One of the authors (Scott Butler) is a former employee of Pfizer. This does not alter our adherence to all PLoS Pathogens policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: KW SLB EOF. Performed the experiments: KW FS KN. Analyzed the data: KW SRD FS KN SLB EOF. Contributed reagents/materials/analysis tools: SRD SLB. Wrote the paper: KW EOF.