Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, Tokyo 113–0033, Japan (T.H., R.I., S.S., T.N., H.N., A.N.); Department of Biology, Faculty of Science, Ochanomizu University, Otsuka, Tokyo 112–8610, Japan (N.S.); and Department of Life Science, College of Science, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Tokyo 171–8501, Japan (T.M., H.K., T.K.)(At 2006-08-25)
