BMP4 inhibits skeletal but not cardiac myogenesis. Panel I: P19[BMP4] and P19[control] cells were aggregated in the presence of 0.8% dimethylsulfoxide (DMSO). Cells were fixed on day 9, stained with MF20 antibody (A-D), and counter-stained with Hoechst dye to show the nuclei (E-H). Magnification is 400x. Panel II: The number of MHC+ve cells were counted and the average +/- standard error of mean shown. Statistics were Student's t-test, *P < 0.05, n = 3.