Fig. 9.

MiR-27a and b promoters are responsive to slow-twitch-associated signaling factors. Activity of the mouse miR-27a (A) and mouse C9orf3 (B) upstream promoter regions in C₂C₁₂ myotubes with cotransfection with a GFP control plasmid, a constitutively active calcineurin (ca-CN) plasmid, a constitutively active nuclear factor of activated T cells (ca-NFAT3) plasmid, a wild-type myocyte enhancer-factor-2C (MEF-2C) plasmid, and a wild-type peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) plasmid. Cotransfection with the constitutively active calcineurin construct increased activity of both the miR-27a and the C9orf3 promoters, and MEF-2C and PGC-1α cotransfection increased activity of the miR-27a promoter construct. Bars represent means ± SE for n = 3 different experiments with 6 wells per experiment. *Significantly different from GFP-cotransfected control for each promoter, P < 0.05.