1. Faculty of Life and Environmental Science, University of Yamanashi, Kofu 400-8510, Japan
2. Advanced Biotechnology Center, University of Yamanashi, Kofu 400-8510, Japan
3. Present: Kameda Medical Center, Chiba 296-8602, Japan
4. Present: RIKEN Center for Brain Science (CBS), Wako 351-0198, Japan
5. Present: Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba 263–8555, Japan