1. Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan, CREST, Japan Science and Technology Agency, Osaka, Japan, PRESTO, Japan Science and Technology Agency, Osaka, Japan, Daiichi Suntory Biomedical Research Company, Ltd., Shimamoto, Osaka 618-8513, Japan, and Suntory Institute for Bioorganic Research, Shimamoto, Osaka 618-8503, Japan