1. Chemical Genetics Laboratory; RIKEN Advanced Science Institute; Wako Saitama 351-0198 Japan
2. Institute for Virus Research; Kyoto University; Sakyo-ku Kyoto 606-8507 Japan
3. Drug Research Laboratories; Kyowa Hakko Kirin Co., Ltd; Nagaizumi Shizuoka 411-8731 Japan
4. Laboratory for Malignancy Control Research; Medical Innovation Center; Kyoto University Graduate School of Medicine; Sakyo-ku Kyoto 606-8507 Japan