Figure 1. Treatment of 293 cells with UV irradiation stimulates phosphorylation of c-Jun at Ser63 but does not affect the level of total c-Jun. The relationship between lysate protein concentration from untreated and UV-treated 293 cells and the absorbance at 450 nm using the FastScan™ Total c-Jun ELISA Kit #23176 is shown in the upper figure. The corresponding western blots using phospho-c-Jun (Ser63) antibody (left panel) and c-Jun antibody (right panel) are shown in the lower figure. 293 cells were treated with UV (50 mJ/cm<sup>2</sup> with 60 min recovery at 37ºC) and then lysed.