1. Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
2. Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
3. Forschungszentrum Jülich, ICS-6, Jülich, Germany
4. Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Biologie and BMFZ, Düsseldorf, Germany