DUSP26 protects against acute kidney injury by dephosphorylating p53 at serine 312.

Acute kidney injury (AKI) remains a leading cause of morbidity and mortality, yet the molecular pathways driving kidney tubule damage in AKI are not fully understood. Here, we report dual-specificity phosphatase 26 (DUSP26) as a critical regulator of kidney tubule injury in AKI. In our study, DUSP26 expression was markedly reduced in kidney biopsies from AKI patients of both sexes and in male murine models of cisplatin nephrotoxic and ischemic AKI. This down-regulation was driven by hypermethylation of the gene promoter of DUSP26 in kidney tubular cells. Loss of DUSP26 exacerbated tubular damage, whereas knock-in of DUSP26 specifically in kidney proximal tubule cells conferred protection. Mechanistically, DUSP26 directly bound to p53 to dephosphorylate it at serine 312, dampening the transcriptional activity of p53 towards cell death genes. Pharmacologic inhibition of DUSP26 sensitized kidneys to AKI, whereas DUSP26 overexpression was protective. Pharmacologic inhibition of DUSP26 also exacerbated ischemia-reperfusion injury in the liver. These findings uncover DUSP26 as a key phosphatase guarding against tissue injury by dephosphorylating p53 at serine 312, and highlight the DUSP26-p53 axis as a promising therapeutic target.