In this study, we have used our highly enriched and functionally validated iPSC-derived, patient specific motor neuron model2,12,13 to systematically investigate the effects of ALS-causing VCP mutations on RBP nucleocytoplasmic localization and the ability of an inhibitor of the VCP D2 ATPase to suppress these VCP-related disease phenotypes. The gene discussed is VCP; the disease is amyotrophic lateral sclerosis.