Fig. 1.

Neurofibromin and Pten loss in astrocytes results in increased mTOR-dependent proliferation. Whereas Nf1^−/− (A) and Pten^−/− (B) astrocytes exhibit increased mTOR activation (phospho-S6 Ser-240/244) and proliferation sensitive to 10 nM rapamycin inhibition (C and D), Tsc1-deficient (E) and Rheb-expressing (F) astrocytes exhibit robust mTOR activation but no increase in proliferation in vitro. Total S6 and α-tubulin were included as internal loading controls. Asterisks denote statistically significant differences (P ≤ 0.0001) between WT and Nf1^−/− or Pten^−/− astrocytes. Bars indicate SEM.