Figure 3

The AMPK pathway acts as a key regulator for suppressing mTOR phosphorylation during PPV infection. A, B PTCs were pre-treated with solvent (DMSO), LY294002 (a PI3K/Akt inhibitor, 10 μM), PFTα (a p53 inhibitor, 10 μM), Compound C (an AMPK inhibitor, 10 μM), PFTα (a p53 inhibitor, 10 μM), or PD98059 (a MAPK/ERK1/2 inhibitor, 20 μM), and cell viability was determined by MTT assay (A). Then, PTCs were infected with PPV (MOI = 1) for 12 h after being pre-treated with the above inhibitors. The level of LC3 II was evaluated by Western blotting (B), and the ratio of LC3 II/β-actin was calculated and analysed (C). (D-H) PTCs were pre-treated with Compound C (10 μM) or the same volume of DMSO and then infected with PPV (MOI = 1) or mock for 12 h. The levels of the indicated cellular proteins were evaluated by Western blotting (D), and the ratios of p-AMPK to AMPK, p-mTOR to mTOR, and Beclin1 and LC3 II to β-actin as reported in D were calculated and analysed (E–H). The results are presented as the mean ± SEM (SD) of three experiments, * p < 0.05; ** p < 0.01.