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Although mTOR (the mammalian target of rapamycin) can regulate intracellular free Ca²⁺concentration in normal cultured podocytes, it remains elusive as to how mTORC2/AKT-mediated Ca²⁺participates in the process of T-2 toxin-induced apoptosis. The potential signaling responsible for intracellular Ca²⁺ concentration changes was investigated using immunoblot assays in an in vitro model of TM3 cell injury induced by T-2 toxin. Changes in Ca²⁺ were assessed using the Ca²⁺-sensitive fluorescent indictor dye Fura 2-AM. The cytotoxicity of TM3 cells was assessed with an MTT bioassay, and apoptosis was measured using Annexin V-FITC staining. Following T-2 toxin treatment, the growth of cells, phospho-mTORSer2481, phospho-mTORSer2448, and phospho-AktSer473 were significantly decreased in a time-dependent manner, whereas Ca²⁺ and apoptosis were increased. T-2 toxin-induced apoptosis was prevented by BAPTA-AM (a Ca²⁺chelator) and MHY1485 (an mTOR activator), and the application of mTOR activator MHY1485 also prevented the increase of intracellular free Ca²⁺concentration in TM3 cells. Our results strongly suggest that T-2 toxin exposure induces apoptosis in TM3 cells by inhibiting mTORC2/AKT to promote Ca²⁺ production.