1. K. Kimura, M. Amano, K. Chihara, Y. Fukata, M. Nakafuku, K. Kaibuchi, Division of Signal Transduction, Nara Institute of Science and Technology, Ikoma 630-01, Japan.
2. M. Ito, B. Yamamori, J. Feng, T. Nakano, First Department of Internal Medicine, Mie University School of Medicine, Tsu 514, Japan.
3. K. Okawa and A. Iwamatsu, Central Laboratories for Key Technology, Kirin Brewery Company Limited, Yokohama 236, Japan.