Fig. 7.

Temporal patterns of miRNA expression in vitro and in vivo. In vitro miRNA expression in proliferating or differentiating MPC was determined by quantitative PCR array. In vivo miRNA expression was measured by quantitative real-time PCR at baseline (day 0) and at various days (day 1 through day 21) after cardiotoxin injection. A: expression of miR-1 and -499 during MPC differentiation in vitro (#P < 0.001 compared with day 0) and during in vivo muscle regeneration (*P ≤ 0.002 compared with day 0). B: expression of miR-682 during the proliferation of cultured MPC (#P = 0.02, day 2 compared with day 5) and during in vivo muscle regeneration (*P ≤ 0.003 compared with day 0). Data represent means ± SD of 4 different MPC primary cultures with the cell proliferation or differentiation assays initiated at passage 3 or 4 mice per time point during in vivo muscle regeneration.