1. Center for Molecular Biology and Neuroscience and Institute of Medical Microbiology, Oslo University Hospital, Oslo, Norway
2. Department of Molecular Biosciences, University of Oslo, P.O. Box 1041 Blindern, N-0316 Oslo, Norway
3. Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, N-7489 Trondheim, Norway
4. Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
5. Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1018 Blindern, N-0315 Oslo, Norway