FIG. 1.

The expression profiles of SOCS and PIAS during myogenic differentiation. (A) Total RNA was isolated from C2C12 cells harvested at different time points as indicated and then subjected to semiquantitative RT-PCR analysis to detect the mRNA levels of eight SOCS family members and four PIAS family members. (B) WCE was prepared from C2C12 cells harvested at different time points as indicated. SOCS1, SOCS3, and PIAS1 proteins were separately immunoprecipitated (IP) from 500 μg of WCE and then subjected to Western blotting (WB) with the same set of antibodies for detection. For both (A) and (B), myogenin was used as an early differentiation marker. Several independent experiments were performed with similar results, and a representative is shown.