YOD1 promotes renal fibrosis by stabilizing JAK2 through deubiquitination
Renal fibrosis is an important pathological change in the development of progressive kidney diseases. Ubiquitination is a post-translational modification of proteins involved in the regulation of various pathophysiological processes. In this study, we found that the deubiquitinating enzyme YOD1 is significantly upregulated in the kidney tissues of Ang II-challenged mice and Ang II upregulates YOD1 expression in renal tubular epithelial cells. YOD1 deficiency significantly alleviated renal injury and fibrosis induced by Ang II infusion in mice. Mechanistically, RNA-seq and co-immunoprecipitation analysis showed a pro-fibrotic protein, JAK2, as a YOD1-binding protein. We identify that JAK2 interacts with the C-terminal Znf domain of YOD1. YOD1 removed K48-linked ubiquitination of JAK2 at residue K970 via its active site C155, which stabilizes JAK2 and then maintains JAK2/STAT3 signaling pathway activation to induce pro-fibrotic gene expression in renal tubular epithelial cells. JAK2 inhibitors reversed the renal fibrosis promoted by YOD1 in mice. We also show increased levels of YOD1 and JAK2 in the kidney tissues of patients with renal fibrosis. In addition, YOD1 knockout significantly prevents unilateral ureteral ligation (UUO)-induced renal fibrosis in mice. Collectively, these findings identify YOD1 as a novel regulator in renal fibrosis via deubiquitinating JAK2. Overall design: We utilized transcriptome sequencing (RNA-seq) to identify candidate pathways regulated by YOD1 in Ang II-treated TCMK1 cells.