1. Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund 44227, Germany
2. The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, EH9 3BF, United Kingdom
3. International Max Planck Research School (IMPRS) in Chemical and Molecular Biology, Max Planck Institute of Molecular Physiology, Dortmund 44227, Germany