Fig. 3. L- and S-endoglin expression and their effects on TGFβ receptors. (A) Immunofluorescence and (B) western blot of endoglin in L₆E₉ mock, L-endoglin (L-Endo) and S-endoglin (S-Endo). (C,D) Mock-, L-Endo- and S-Endo-transfected cells were serum starved for 24 hours before TGFβ1 treatment. The expression of ALK1, ALK5 and TβRII in control (C), or TGFβ1-treated (T) cells was analyzed by RT-PCR (C) and western blot (D). A representative blot from three independent experiments is shown.