Fig. 7.

The NOS2-2 protein is functional. DLD-1_TR7 cells stably expressing a tetracycline repressor were transiently transfected with pcDNA4/TO_NOS2-1_cds_3UTR or pcDNA4/TO_NOS2-2_cds_3UTR encoding the NOS2-1 or -2 protein. To normalize the transfection efficiency, pRL-EF1α (encoding for a renilla luciferase) was cotransfected as well. After transfection, the cells were incubated with (Tet) or without (co) 500 ng/ml tetracycline for 24 h. Then the supernatants of the cells were used for nitrate concentration determination by the Griess assay. The cells were lyzed and renilla luciferase activity was measured. The nitrate concentrations determined were normalized to the renilla luciferase data. Shown is the summary of the analysis of the four different transfection experiments. The values represent the mean ± SEM of n = 8 different wells, (***p < 0.001; *p < 0.05, ns not significant;1-way Anova with Dunnett's multiple comparisons test)