FIG. 6.

Direction interaction between MyoD and CREB1. (A) CREB1 and the indicated deletion proteins were generated by in vitro translation in the presence of [³⁵S]methionine using the TNT SP6 coupled reticulocyte lysate system (Promega). ³⁵S-labeled proteins were revealed by autoradiography. (B) Direct interaction of MyoD with the bZIP domain in CREB1. ³⁵S-labeled CREB1 constructs were incubated with recombinant GST-MyoD protein (full length) immobilized on agarose beads. After washing, bead-bound proteins were resolved by SDS-polyacrylamide gel electrophoresis and autoradiography. (C) GST-beads did not interact with ³⁵S-labeled CREB1 constructs. (D) Interaction between endogenous MyoD and CREB1 in muscle cells. Lysates of C2C12 cells were incubated with anti-CREB1 antibody or an irrelevant antibody (control), and resulting complexes were probed with anti-MyoD antibody. IP, immunoprecipitation; IB, immunoblotting.