1. Department of Physiological Genomics, Biomedical Center Ludwig‐Maximilians‐University Großhaderner Str. 9 D‐82152 Planegg‐Martinsried Germany
2. Institute for Stem Cell Research, German Research Center for Environmental Health Helmholtz Centre Munich Ingolstädter Landstraße 1 D‐85764 Neuherberg Germany
3. Institute for Pathophysiology University Medicine Greifswald Martin‐Luther‐Str. 6 17489 Greifswald Germany
4. Neuromuscular Research Department Center for Anatomy and Cell Biology Medical University of Vienna Waehringerstrasse 13 1090 Vienna Austria