Mie University - Department of Microbiology and Molecular Genetics, Mie University - Department of Microbiology and Molecular Genetics, University of Tokyo - Division of Virology, RIKEN-JEOL Collaboration Center - Multi-Modal Microstructure Analysis Unit, RIKEN-JEOL Collaboration Center - Multi-Modal Microstructure Analysis Unit, Mie University - Department of Microbiology and Molecular Genetics, University of Tokyo - Division of Virology, University of Tokyo - Division of Virology, University of Tokyo - Division of Virology, RIKEN-JEOL Collaboration Center - Multi-Modal Microstructure Analysis Unit, University of Wisconsin-Madison - Influenza Research Institute and Mie University - Department of Microbiology and Molecular Genetics