Affiliation: | a Departments of Biological Sciences, Tokyo Institute of Technology, 4259-B-19 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan b Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima 411-8540, Japan c Department of Biology, University of Pennsylvania, Lynch Laboratories 204E, Philadelphia, PA 19104-6017, USA |