BMP9-dependent induction of SDF1 expression is promoted by endoglin and is dependent on endothelial cell type. (A) The ligand specificity for the upregulation of SDF1 expression in HAEC and HMVEC-C was analyzed by RT-PCR after treatment with 5 ng/mL BMP9 or 10 ng/mL TGF-β1. (B) RT-PCR of HMVEC-C demonstrated upregulation of endoglin in response to treatment with BMP9 (5 ng/mL, 24 hours) and is impaired by endoglin suppression. (C) Real-time quantitative RT-PCR of endoglin and SDF1 cDNA induction by BMP9 in HAECs, in the presence of control shNT or shENG suppression. (D) Quantitative RT-PCR of SDF1 cDNA induction by BMP9 in HMVEC-C and HMVEC-D cell culture in the presence of control shNT or shENG suppression. Error bars represent mean ± SE for 3 experiments.