Fig. 3.

Western blot analysis of bone morphogenetic protein-3 (BMP3) and PSmad protein expression. A: Western blot of conditioned media from DF1 cells infected with replication competent avian retroviral vector (RCAS) -BMP3 or RCAS-AP. A 30-kDa BMP3 band is only detected in the RCAS-BMP3–infected cells. As a positive control, conditioned media from CHO cells transfected with human BMP3 was used (left lane). B: Western blot of extracts from RCAS-BMP3–infected and uninfected limb buds collected on day 5 using anti-PSmad 1, 5, 8 antibody to evaluate BMP signaling. The blot was stripped and anti-Smad 1, 5, 8 antibody was used to detect total Smad 1, 5, 8 protein as a loading control. Limbs infected with BMP3 had decreased levels of PSmad 1, 5, 8 when compared with controls.