To ascertain whether rFGF4 protects against renal injury through podocyte FGFR1, podocyte-specific Fgfr1 knockout (Fgfr1-PKO) mice were generated and subjected to STZ-induced diabetes, followed by rFGF4 or PBS vehicle treatment (Fig. 4f and Supplementary Fig. 9a, b). Here, FGFR1 is linked to diabetes mellitus.