1. From the Institute for Molecular and Cellular Biology, Osaka University, Yamada-oka, Suita, Osaka, Japan; the Life Science Group, Faculty of Integrated Arts and Sciences, Hiroshima University, Kagamiyama, Higashihiroshima, Hiroshima, Japan; and Hitachi Software Engineering, Co, Ltd, Onoe-chou, Naka-ku, Yokohama, Japan.