1. Center for Gene Research, Yamaguchi University, 1–1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan;
2. Division of Molecular Membrane Biology, Cancer Research Institute, Kanazawa University, Kanazawa 920-0934, Japan; and
3. Department of Microbiology and Immunology, Kagoshima University Dental School, 8–35-1 Sakuragaoka, Kagoshima 890-8544, Japan