Fig. 3. MyoD is unable to upregulate expression of p27^Xic1 in vivo. (A) Quantitative RT-PCR for MA, p27^Xic1 and ODC on cDNA from animal caps of embryos injected with 100 pg MyoD. (B-F') Embryos were injected with 100 pg MyoD (B,C,F,F') or 50 pg DNMyoD (D,E) into one cell of two-cell stage embryos, along with ß-gal as a tracer (light blue, injected side towards the left in B-E or upwards in F,F'). Dorsal views of embryos analyzed for (B,D) MA or (C,E) p27^Xic1 expression by whole-mount in situ hybridization at stage 15 (F,F'). (F,F') MyoD-injected embryos allowed to develop to stage 21 were stained for phospho-histone-H3 then longitudinally sectioned and stained for MA (red) and Hoechst (blue, DNA specific). MyoD overexpression enlarges the area staining for MA (F) and also causes extra proliferation (F', arrows).

Return to article