Insulin-Like Growth Factor-I E-Peptide Activity Is Dependent on the IGF-I Receptor
Figure 7
E-peptides inhibit myoblast differentiation.
A–C. C2C12 cells were grown to confluency and switched to differentiation media (Day 0). Media was changed every day and synthetic peptides (100 nM) were added to the fresh media. Quantitative RT-PCR was used to measure expression of differentiation markers: MyoD (Myod, A), Myogenin (Myog, B), Embryonic Myosin (Myh3, C). Expression of the markers at Days 1, 2, and 3 were compared to Day 0 to obtain fold change. Bars represent fold change means ± s.e.m. of N = 3 replicates. *, p<0.05 for fold change expression comparisons via 2-way ANOVA followed by a Bonferroni post-test. D. Synthetic EA and EB peptides were incubated with growth media and aliquots were taken at times indicated for immunoblotting analysis. E–F. Quantification of (D) and analysis of peptide half-life. Bars represent percent of original intensity ± s.e.m. of N = 3 replicates.
