Fig 1: The p38 MAPK pathway was activated by BPIV3 infection. The MDBK cells were collected in mock-infected group or BPIV3-infected group (MOI = 1) from 6 to 24 h. MKK3, p38 phosphorylation and total amount of p38 were analyzed in whole-cell lysates by Western blot. The primary antibodies were the specific anti-phospho-p38 antibodies (mouse, 9216, CST, USA), anti-p38 antibodies (rabbit, 41666, CST, USA) and anti-MKK3 antibodies (rabbit, 5674, CST, USA), the second antibodies were goat anti-mouse and goat anti-rabbit IgG. β-actin probed with specific monoclonal antibody was served as internal control. Densitometry scans were conducted by ImageJ software (NIH, USA). Densitometry of the phospho-p38 band was normalized to p38, which was presented as fold change ± SEM compared with the mock-infected control defined as 1. These data were from three independent experiments. Significant differences compared with mock-infected control are denoted by *(P < 0.05), ** (P < 0.01). The Same densitometry analysis and statistical analysis were performed in the following experiments. A The protein expression in p38 MAPK pathway by Western blot; B Expression of MKK3; C Expression of p-p38; D Expression of p38