Figure 6.

Activin B (ACT B) uses the type II receptors ACVR2A and ACVR2B to stimulate both SMAD3 signaling and hepcidin in Hep3B cells. Hep3B cells were transfected with control siRNA (CTRL), siBMPR2, siACVR2A, or siACVR2B (40nM), either alone (A) or in combination with CAGA-Luc and pRL-TK (B and C). Forty-eight hours after transfection, cells were incubated in the absence or presence of 5-ng/mL ACT B, BMP6, or activin A (ACT A) as indicated for 6 hours, followed by measurement of HAMP relative to RPL19 mRNA levels by qRT-PCR (A) or relative luciferase activity (B and C). Data are expressed and analyzed as described in Figure 4.