Tautomycin, an antifungal antibiotic isolated from the bacterium Streptomyces verticillatus, is a potent and specific inhibitor of protein phosphatases 1 and 2A and induces contraction of smooth muscle under Ca²⁺-free conditions, with K_iapp values of 0.16 nM and 0.4 nM for PP1 and PP2A, respectively^[1][2]. IC50 & Target: Kiapp: 0.16 nM (PP1), 0.4 nM (PP2A)^[1]. In Vitro: MTC cell growth is inhibited in a dose-dependent manner by Tautomycin (0-1000 nM, 48 hours)^[2].
NE markers ASCL1 and CgA in human MTC cells are decreased in a dose-dependent manner by Tautomycin (0-1000 nM, 48 hours)^[2].