Fig. 7: MMP3 functions downstream of IGF2BP3 in CM proliferation.

A–C Overexpression of MMP3 in P7 CMs promotes cell proliferation, as revealed by flurescence staining (A), flow cytometry sorting (B), and western blot analysis (C) of cell cycle-related proteins. Statistical analyses of proliferating cells stained by EdU, pH3, and Ki67 were performed using 500–600 cells from 6 independent samples in each condition (*P < 0.05; **P < 0.01). Scales bar: 50 µm. D Western blot analysis shows that overexpression of MMP3 rescues the inhibitory effects of IGF2BP3 knockdown on the expression of cell cycle-related proteins. E Knockdown of MMP3 in P1 CMs decreases cell proliferation. Scale bar: 50 µm. For each condition, about 600 cells from six independent samples were included in statistical analyses (**P < 0.01). F Overexpression of MMP3 rescues the inhibitory effects of IGF2BP3 knockdown (designated as KD) on P1 CM proliferation. Scale bar: 50 µm. For each condition, about 600–900 cells from six independent samples were included in statistical analyses (*P < 0.05; **P < 0.01). G Flow cytometry analysis shows that overexpression MMP3 rescues CM proliferation inhibited by IGF2BP3 knockdown (*P < 0.05). H Flow cytometry analysis shows rescue effects of MMP3 overexpression on cell cycle progression inhibited by IGF2BP3 knockdown (*P < 0.05; **P < 0.01).