Figure 2: MyoD expression and myogenic differentiation in miR669a-tranduced Sgcb-null cardiac progenitors after single infection and FACS. The slightly increase in miR669a expression in transduced cells(A, left panel) was able to reduce MyoD expression(A, right panel), and consequently Sgcb-null cardiac progenitors slowed down their myogenic differentiation (B), as showed by a reduction of MyHC positive myotubes.A8, F5,G8 clones were isolated from miR669a-transduced Sgcb-null cardiac progenitors, previously sorted for GFP expression (LV1 GFP+). The fusion index (FI) analysis confirmed the myogenic impairments in transduced clones. Indeed, clones (A8 and G8) that expressed higher level of miR669a resulted in lower number of myotubes and FI (as reported below the panels) compared to the clone (F5) with low miR669a expression. Scale bar = 100 µm.AL