Fig. 3.

Conditional expression of Rheb in astrocytes does not increase cell growth in vitro. (A) Conditional targeting strategy for the generation of LSL-Rheb mice (line 13431). (B) Ad5 virus-mediated Cre delivery results in eGFP (Left; immunofluorescence microscopy) and Rheb (Right; Western blot) expression compared with LacZ delivery. Both eGFP and Rheb expression in Cre-transduced astrocytes is eliminated with doxycycline. (C) Cre-mediated Rheb expression results in increased mTOR signaling (phospho-S6 Ser-240/244 and Ser-235/236). (D) No change in astrocyte proliferation was observed following Cre-mediated Rheb expression as assessed by [³H]thymidine incorporation. Bars indicate SEM.