This peptide is a specific inhibitor for calcineurin (PP2BA), a Ser/Thr protein phosphatase from the PPP family and PP2B subfamily. The peptide corresponds to the residues 467-491 within the inhibitory domain of human calcineurin alpha subunit. Calcineurin is known to dephosphorylate heat shock protein beta-1 (HSPB1) and protein phosphatase Slingshot homolog 1 (SSH1). This peptide inhibits Mn2+-stimulated calcineurin activity (IC50 = 10 uM using 32P-myosin light chain as substrate) but has no effect on Ni2+-stimulated enzyme activity. It does not inhibit CaMKII kinase, protein phosphatase 1 or 2A.Ile-Thr-Ser-Phe-Glu-Glu-Ala-Lys-Gly-Leu-Asp-Arg-Ile-Asn-Glu-Arg-Met-Pro-Pro-Arg-Arg-Asp-Ala-Met-Pro or ITSFEEAKGLDRINERMPPRRDAMP