ERK1/2 signalling is activated early in CPV infection.

<p>(A) Activation of ERK1/2 was analyzed based on phosphorylation of ERK1/2 (p-ERK1/2). Cell lysates were collected at indicated time points post infection and immunoblotting with antibody towards ERK or p-ERK1/2 was performed. (B) Intensity of band signals were determined with densitometry (ImageJ software) and ratio of p-ERK to ERK was calculated. * The difference is statistically significant (p≤0.05) between marked time point and mock infected cells (m, mock infected 6 h p.i.; U, U0126). (C) CPV infection was carried out in the presence of 20 µM U0126 that inhibits the activation of ERK1/2. At 24 h p.i. cells were fixed and CPV infected cells were visualized with anti-capsid antibody. Infection percentage was determined with immunofluorescence microscopy. The observed decrease in infection percentage was statistically significant (p≤0.05). (D) Cells were infected with CPV or mock infected with or without 20 µM U0126 and JC-1 was used to detect the depolarization of mitochondrial membrane potential. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0086124#s3" target="_blank">Results</a> are shown as mean of relative amount of cells showing mitochondrial depolarization from three repeats.