Summary of the results.

In HK-2 cells, oxidative stress induced pri-miR-200c and miR-200c, a miRNA that is complementary with the 3′-UTR of KLOTHO mRNA at two different sites. miR-200c binds to the KLOTHO mRNA 3′-UTR with Argonaute protein (AGO) to suppress the expression of KLOTHO by inhibiting translation. Transfection of a miR-200c mimic reduced KLOTHO expression without a reduction in KLOTHO mRNA levels and transfection of a miR-200c inhibitor maintained KLOTHO expression.