Figure 5.

ERK 1/2 was reactivated in a GGPPS-dependent manner. A: Beas-2B cells infected with adenovirus carrying the scrambled control were exposed to 10% cigarette smoke extract (CSE) for as long as 10 hours, and protein samples were collected at the indicated times and subjected to Western blotting. We also found two peaks of ERK 1/2 activation after CSE stimulation: one at 10 minutes and one at 4 hours. B: When the cells were infected with adenovirus carrying the GGPPS small-interfering RNA before the 10% CSE challenge, the second peak activation of ERK 1/2 at 4 hours disappeared. C: The light density analysis of phosphorylated ERK 1/2 in panels A and B. The data are normalized by total ERK 1/2 expression and expressed as a fold induction with respect to the value of the time point at 0 hours. The light density was calculated using ImageQuant software.