1. Brain Research Institute, University of Zurich, 8057 Zurich, Switzerland
2. Department of Biology and Department of Health Sciences and Technology, ETH Zurich, 8057 Zurich, Switzerland
3. Department of Neurosurgery, University Hospital Zurich, University of Zurich, CH-8091, Zurich, Switzerland
4. Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, CA 95064, USA