Institution: | 1. Division of Molecular Embryology, DKFZ, Heidelberg Germany ; 2. Max Planck Institute of Molecular Cell Biology and Genetics, Dresden Germany ; 3. INSERM, CNRS, iBV, Université Côte d''Azur, Nice France ; 4. Institute of Molecular Biology (IMB), Mainz Germany ;5.Present address: Department of Biology, Institute of Biochemistry, ETH (Eidgenössische Technische Hochschule), Zürich Switzerland |