Fig. 6.

Knockout of the upstream repressor of mTOR, TSC1, alters vasculogenic signaling in the murine lung. Wild-type (A–C) and TSC1^−/− (D–F) embryonic day (E) 12.5 murine fetuses were sectioned and stained for mTOR activity [S6K1 (T389) phosphorylation], VEGF, and Tie2 expression. Arrows in A indicate raised mTOR activity at sites of airway epithelial outgrowth in wild-type animals. Arrows in C indicate Tie2 receptor expression corresponding to nascent vascular bundles. Images are representative of 4 fetuses from independent litters. Bar = 200 μm.