FIG. 3.

Effect of overexpression of dominant-negative p38 on phosphorylation of p38 MAP kinase in AZ-521 cells. AZ-521 cells transfected with pcDNA3 control vector (A) or Flag-tagged dominant-negative p38 construct (B) were incubated with 120 nM VacA for 0, 5, 10, 30, or 60 min. Whole-cell lysates were prepared and resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Western blot analysis was performed with a phosphorylation-specific p38 MAP kinase antibody. The blot was then stripped and reprobed with a p38 MAP kinase antibody to determine equivalent loading of each lane. Data are representative of three separate experiments. (C) Relative densities of phospho-p38 as determined by densitometry scan analysis were compared to densities obtained at 0 min as a control. Data are means ± standard errors of values from triplicate experiments. *, P < 0.01.