Figure 6.

cGAS activates cGAMP activity during PRRSV infection, and cGAMP inhibits PRRSV replication. (A) Marc-145 cells were transfected with p3xFlag, p3xF-cGAS, and infected with or without PRRSV. The cGAMP activity was measured by qRT-PCR to detect the transcript levels of IFNb1. The statistical significance of differences was determined using the Student’s t-test (*p <0.05; ns, not significant). (B) The Marc-145 cells were treated with cGAMP for 12 h at different concentrations and then infected with PRRSV at 0.5 MOI. The cells were harvested at 12 and 24 hpi. The N protein level was detected by WB with anti-N pAb. (C) The Marc-145 cells were treated with cGAMP of 10 μg/ml for 12 h, and the cells were infected with PRRSV at 0.5 MOI. The cells were harvested at a different time, and the N protein was detected by WB with the anti-N pAb.