Figure 2.

lncMUMA Expression Associated with Muscle Differentiation in Microgravity-Simulated C2C12 Myoblasts In Vitro and Muscle Mass in HLS Mice

(A) Real-time PCR analysis of lncMUMA levels in C2C12 cells with either normal gravity (control) or microgravity-simulated (MGS) culture environment on days 0, 1, 3, 5, and 7 of differentiation. (B) Western blot analysis of MyoD protein level in C2C12 cells with either normal gravity (control) or MGS culture environment on days 0, 1, 3, 5, and 7 of differentiation. (C) Representative images of C2C12 cells with either normal gravity (control) or MGS culture environment on day 7 of differentiation. Myosin was labeled with green fluorescence and the nuclei were labeled with DAPI. Scale bars, 50 μm. (D) The fusion index in C2C12 cells with either normal gravity (control) or MGS culture environment on day 7 of differentiation. (E) Real-time PCR analysis of lncMUMA levels in gastrocnemius muscle of either age-matched control or HLS mice. (F and G) Representative images (F) and muscle mass (G) of gastrocnemius muscle from age-matched control and HLS mice during unloading. Scale bar, 5 mm. n = 5 for in vitro and n = 10 for in vivo. U6 small nuclear RNA is used as the endogenous control of lncRNA. β-actin is used as the endogenous control for protein. Data are presented as mean ± SEM. *p < 0.05 versus the corresponding day 0.