The ets element at position −68 contributes to the transcriptional activity of the endoglin promoter. BAEC were transiently transfected with the pCD105 (−81/+350) (wild-type) or pCD105 (−81/+350)-Mut (ets mutant), which contains a mutation at the ets site (A). The luciferase activity was determined 48 hours after transfection. Correction for transfection efficiency was made by cotransfection with β-galactosidase expression vectors and parallel transfections with the pGL2-SV40 and pXP2 vectors, used as positive and negative controls, respectively. This is a representative experiment of three separate experiments.