1. Department of Anatomy and Cell BiologyCarver College of Medicine, University of Iowa Iowa City IA 52242 USA
2. Key Laboratory of Medical Electrophysiology of Ministry of EducationMedical Electrophysiological Key Lab of Sichuan ProvinceInstitute of Cardiovascular Research of Southwest Medical University Luzhou 646000 China
3. Electron Microscopy FacilityMax Planck Florida Institute for Neuroscience Jupiter FL 33458 USA
4. Research Group Molecular Mechanisms of Synaptic FunctionMax Planck Florida Institute for Neuroscience Jupiter FL 33458 USA
5. Department of Biochemistry Graduate School of Medicine/Faculty of MedicineUniversity of Yamanashi 1110 Shimokato Chuo Yamanashi 409‐3898 Japan
6. Department of Otolaryngology, Iowa Neuroscience InstituteCarver College of Medicine, University of Iowa Iowa City IA 52242 USA