New insights into mTOR signaling: mTORC2 and beyond.

The mammalian target of rapamycin complex 2 (mTORC2) plays critical roles in regulating cell growth and proliferation. mTORC2 promotes the activation of the serum glucocorticoid-induced protein kinase (SGK). This mTOR complex also promotes the constitutive phosphorylation of proline-directed serine or threonine sites in the turn motif of Akt and protein kinase C isoforms. mTORC2 may control phosphorylation of the turn motif by promoting the activity of a kinase that targets the Ser/Thr-Pro sequence or by inhibiting the activity of a phosphatase.