Figure 5.

Deliberate activation of p38 induces NF-κB-dependent transcription in C2C12 myoblasts cultured in serum-free medium. The reporter construct p6×NF-κB-Luc was transiently transfected into C2C12 cells, in the presence or absence of expression plasmids for MKK6(E), MKK6(A), IκBα(S32,36A) or empty vector, respectively, and luciferase activities were analyzed after 36 h in DMEM. When indicated, SB203580 was added to DMEM. pRSV-lacZ plasmid was used as a transfection control, and the corresponding β-galactosidase activities were used to normalize the luciferase values. Luciferase activities are expressed relative to the activity of the reporter plasmid (cotransfected with empty vector) in DMEM, which was given a value of 1. Error bars represent the SE of the mean value.