1. Department of Neurology, University of Michigan, Ann Arbor, United States
2. Cell and Molecular Biology Program, University of Michigan, Ann Arbor, United States
3. Department of Cell Biology, Columbia University Medical Center, New York, United States
4. Center for Motor Neuron Biology and Disease, Columbia University Medical Center, New York, United States
5. Department of Pathology, Columbia University Medical Center, New York, United States
6. Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, United States