1. Medical Systems Biology, Medical Faculty and University Hospital Carl Gustav Carus, University of Technology, Fetscherstrasse 74, 01307 Dresden, 2Structural Bioinformatics, BIOTEC TU Dresden, Tatzberg 47-51 01037 Dresden and 3Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany