FIGURE 2.

Effects of myoD and ATF-1 on UCP3 murine promoter activity. A, luciferase reporter constructs of mouse UCP3 5′-end promoter region. Numerical annotation is relative to the transcriptional start site designation as +1. B, reporter constructs transfected into C2C12 myoblasts with MyoD or pcDNA empty control vector. Luciferase activities were normalized to the activity of 2k-luc co-transfected with the empty vector (value = 1) and represent mean ± S.D. of three independent experiments in this and all subsequent cotransfection experiments. C, similar study to B, with the exception that the luciferase activity in response to ATF-1 is assessed instead of that of myoD. D, cotransfection experiments to evaluate the combined ex vivo activation capacity of myoD and ATF-1 using the full-length and 2-luc UCP3 promoter-luciferase reporter constructs.