Fig. 3. Fusion of control and TRPC1-knockdown myoblasts into myotubes. C2C12 myoblasts were submitted to a differentiation medium (fetal serum replaced by adult serum in the culture) and were followed during 7 days in culture (D0 to D7). (A) Comparison of the fusion observed at day 7 in C2C12 myoblasts transfected with control shRNA (upper panels) or with TRPC1 shRNA (lower panels). Left panels, light micrographs; right panels, fluorescence micrographs (nuclei stained with Hoechst 33342). Scale bar: 100 µm. (B) Quantification of fusion process: number of nuclei in myotubes / total number of nuclei (where a myotube is defined as having at least three nuclei). Results submitted to Student's t-test: ***P<0.001 vs control, n=6. (C) Comparison (DIC micrographs) of the fusion observed at day 0 (left panels) and day 7 (right panels) in the absence (upper panels) or in the presence (lower panels) of 50 µM ZLL-CHO. Scale bar: 100 µm.