1. Organization for Promotion of Tenure Track, University of Miyazaki, Miyazaki 889-1692, Japan
2. RIKEN BioResource Center, Ibaraki 305-0074, Japan
3. Tsukuba Primate Research Center, National Institute of Biomedical Innovation, Ibaraki 305-0843, Japan
4. Present: Harvard Medical School, Boston, MA 02115, USA