FIG. 5.
Western blot demonstration of the effects of constitutively active MEK1 (CA-MEK1) protein overexpression on MAPK activation (phosphorylated p44/42 [Phospho-p44/42], also known as phosphorylated or activated ERK1/2) and viral multiplication in PDA cultures 4 days post-exposure to 100 HAU of JCV per 5 × 105 cells. CA-MEK1 overexpression was achieved by transfecting PDA cultures with a plasmid that shares the name of this mutant protein. The control transfection was performed with pCDNA3. Blots utilized whole-cell lysates that were resolved on 4 to 12% gradient gels, transferred to a PVDF membrane, and probed with anti-Vp-1, anti-MEK1, anti-Ph-p44/p42, and anti-p44/p42. The anti-p44/p42 blot serves as a total protein loading control. Results included are representative of three independent experiments.