Fig. 6.

Nb1 suppresses BVDV replication of different MOIs and interacts with BVDV-encoded NS5B protein. MDBK, MDBK-Nb35^EGFP and MDBK-Nb1^EGFP cell lines were infected with BVDV at MOIs of 0.1 and 1 for 48 hpi. BVDV-induced CPEs were monitored under an inverted microscope (A). The scale bar indicates 250 μm. BVDV production was analyzed based on TCID₅₀ values (B). BVDV-NS5B protein levels were measured by western blotting with α-tubulin as the control (C). Cell viability was assessed using the CCK-8 method at 48 hpi (D). Interaction between intracellularly expressed Nb1 and BVDV-encoded NS5B in MDBK cells infected with BVDV. MDBK-Nb1^EGFP and MDBK-Nb35^EGFP cell lines were infected with 1 MOI of BVDV, and cells were collected at 72 hpi. Immunoprecipitated proteins were analyzed by western blotting using a mouse anti-GFP monoclonal antibody and a mouse anti-NS5B polyclonal antibody (E). Data are shown as the mean ± SD representative of three independent experiments. p values were calculated using ANOVA. Significant differences, as compared to control values are denoted as ***(p < 0.001).