1. Department of Life Science and Medical Bio-Science, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan, Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan, and J-Bio 21 Corporation, 1-9-8 Higashikanda, Chiyoda-ku, Tokyo 101-0031, Japan