Nedd4-2 can mediate the ubiquitination of epithelial sodium channel (ENaC), voltage-gated sodium channels (Navs) and also the glutamate transporters.27, 28, 29, 30, 31 however, it is unclear whether Nedd4-2-mediated ubiquitination of glutamate transporters plays a role in PD and whether Nedd4-2 may potentially serve as a therapeutic target in PD. This evidence concerns the gene NEDD4L and Parkinson disease.