FIGURE 2.

Induction of Glut4 expression by ZAC1. A, NRC were untreated (C) or infected for 48 h with adenoviruses encoding β-galactosidase (β) or ZAC1 (Z). Total RNA was isolated for RT-PCR, generating a single 554-bp amplicon using Glut4-specific primers. B, NRC were untreated (C), or infected for 48 h with adenoviruses encoding either eGFP (G) or ZAC1 (Z). Total protein was subjected to Western blotting, and a 50-kDa band corresponding to GLUT4 was obtained. C, densitometric analysis of the Western blot data in B, representing three independent experiments. *, p < 0.01 versus control. D, NRC plated on glass coverslips were untreated or infected with an adenovirus encoding ZAC1 for 48 h and then immunolabeled with anti-GLUT4 (red) and nuclei stained with 4′,6-diamidino-2-phenylindole (blue). Scale bar, 25 μm. E, glucose uptake assay was performed, for the indicated time in minutes, in NRC untreated or previously infected with adenoviruses encoding β-galactosidase or ZAC1. Scale bar, 25 μm. F, quantification of data obtained in E, representing three independent experiments, ∼12 cells per data point per experiment. Results were normalized to control at each time point. *, p < 0.05 versus control. GAPDH, glyceraldehyde-3-phosphate dehydrogenase.