作者单位:International Institute for Advanced Studies, 9-3, Kizugawadai, Kizugawa City, Kyoto 619-0225, Japan[1]Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1[2]Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113[3]Institute for Protein Research, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan[4]