Figure 6. Levels of TSC2 and Sestrin2 mRNA and protein in carcinoma cells that are p53 null or that express only mutant p53.
(A) TSC2 protein levels determined by immunoblot of lysates. (B) TSC2 and Sestrin2 mRNA levels were measured by RT-qPCR using total RNA. (mean ± sd, n=3). siRNA depletion of TSC2 (C) or genetic deletion of Sestrin2 (D) substantially increase the level of mTORC1 activity. HCT116 cells wt for p53 were transfected with siRNA against TSC2 or a scrambled control and mTORC1 activity was assessed by phosphorylation of S6K1 at T389 (C). MEFs from mice with genetic deletion of Sestrin2 were likewise probed for pT389-S6K1 (D).