YOD1 Deubiquitinates NEDD4 Involved in the Hippo Signaling Pathway.

ABSTRACT

BACKGROUND/AIMS: Deubiquitinating enzymes (DUBs) are crucially involved in controlling signal transductions, and reverse ubiquitination by removing the ubiquitin from protein substrates. The Hippo signaling has an important role in tissue growth, cell proliferation, differentiation, and apoptosis. Since disruption of the Hippo signaling is associated with a number of diseases, it is imperative to investigate the molecular mechanism of the Hippo signaling. METHODS: DUB screening was performed using the kidney of the mouse unilateral ureteric obstruction (UUO) model to identify the cellular mechanism of the DUB-regulated Hippo signaling. In addition, kidney cells were used to confirm cell proliferation and protein levels in the Hippo signaling pathway. Densitometric analysis was conducted to compare the expression level of proteins using Image J. RESULTS: We found that YOD1, also known as OTU1, is downregulated in the mouse UUO model. We also demonstrated that YOD1 binds to and deubiquitinates neural precursor cell expressed developmentally down-regulated protein 4 (NEDD4). Furthermore, we observed that YOD1 suppresses NEDD4-induced cell proliferation. CONCLUSION: YOD1 regulates the Hippo signaling pathway through NEDD4, and the K63-linked polyubiquitin chain of NEDD4 plays an important role. Also, our results indicate that YOD1 plays an important role in kidney diseases.