Figure 5.
At LD conditions MyoD and p27Kip1 show a major posttranslational control. (A) Northern Blot analysis of p27Kip1 and MyoD transcript accumulation. (B) Kinase activities precipitated by anti-Cdk2 or anti-Cdk4 antibodies from C2C12 at the indicated culture conditions after 24 h in GM or after shifting for 72 h in DM as assayed by phosphorylation of histone H1 (H1) and GST-Rb fusion protein (Rb) respectively. The amount of Cdk2 and Cdk4 in the immunoprecipitates was assessed by Western blot. (C) C2C12 cells, grown in GM at HD or LD were treated with either 50 μM MG132 (MG) or 5 μM Roscovitine (R) for 6 h. (-) denotes treatment with dimethyl sulfoxide. Extracts normalized for protein content (β-tubulin) were probed with antibodies specific for the indicated proteins.