Expression of BMP and BMPRs in HepG2BRA and C2C12BRA cells. Total RNA from C2C12BRA and HepG2BRA cells was isolated and used as a template for the reverse transcriptase-polymerase chain reaction (RT-PCR) to examine the expression of BMP and BMPRs. G3PDH gene expression was used as an internal control. PCR products were separated in 1% agarose gel and visualized after ethidium bromide staining. (A) Representative RT-PCR analysis of total RNA using specific primers for BMP-2, BMP-4, BMP-6 and BMP-7. (B) Representative RT-PCR analysis of total RNA using specific primers for BMP type I receptors (ALK2, ALK3, ALK6) and BMP type II receptors (BMPR-II, ActR-IIA, ActR-IIB). Similar results were obtained in two separate experiments.