Fig 5.

PRV infection activates The PI3K/AKT/mTORC1 and AMPK/mTORC1 pathways via VDR-mediated Ca²⁺ absorption. (A) Heat map of the fold changes of the indicated AMPK signaling pathway genes in scramble and shVDR-2 PK-15 cells mock-infected or infected with PRV-QXX (MOI = 1) as indicated for 24 h. (B) Heat map of the fold changes of the indicated PI3K-AKT signaling pathway genes in scramble and shVDR-2 PK-15 cells mock-infected or infected with PRV-QXX (MOI = 1) as indicated for 24 h. (C) Heat map of the fold changes of the indicated mTOR signaling pathway genes in scramble and shVDR-2 PK-15 cells mock-infected or infected with PRV-QXX (MOI = 1) as indicated for 24 h. (D) PK15 cells were treated with BAPTA-AM (10 µM) as indicated, and simultaneously mock-infected or infected with PRV-QXX (MOI = 1) for 24 h. The protein levels of p-AMPK, AMPK, p-PI3K, PI3K, p-AKT, AKT, p-mTORC1, mTORC1, PRV gB, and β-actin were analyzed by immunoblotting analysis. (E) Scramble and shVDR-2 PK15 cells were infected with RV-QXX (MOI = 0.1) for 0–48 h. The protein levels of p-AMPK, AMPK, p-PI3K, PI3K, p-AKT, AKT, p-mTORC1, mTORC1, VDR, PRV gB, and β-actin were analyzed by immunoblotting analysis. (F-H) PK-15 cells were treated with vehicle, Rap (F, 10 µM), Dor (G, 100 nM), or PF (H, 10 µM) for 0–48 h. Cell proliferation was analyzed by CCK-8 assay. ns, no significance. (I) Scramble and shVDR-2 PK15 cells were treated with Rap (10 µM), Dor (100 nM), and PF (10 µM) as indicated and infected with PRV-QXX (MOI = 1) for 24 h. The viral titer was analyzed by a PFU assay. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001. ns, no significance.