Figure 4

The effect of the NDV M protein on the transcription of the chBRD2 gene. A The expression levels of the NDV M protein in different infection doses of NDV-infected DF-1 cells. DF-1 cells were infected with rSS1GFP at an MOI of 0.01, 0.1 or 1. The expression levels of the M protein in rSS1GFP-infected DF-1 cells were detected at 6, 12 and 24 hpi. The relative expression levels of the M protein compared to control GAPDH expression levels were determined by densitometry using ImageJ software version 1.8.0. Error bars represent standard deviations (mean ± SD) (*P < 0.05; **P < 0.01; ***P < 0.001 compared to the value of the 0.01 MOI group). B Transcription levels of the chBRD2 gene in DF-1 cells infected with different doses of NDV at 6, 12 and 24 hpi. The relative transcription levels of the chBRD2 gene were compared with those of the control GAPDH gene. Error bars represent standard deviations (mean ± SD) (*P < 0.05; **P < 0.01; ***P < 0.001 compared to the value of non-infected cells). C The expression levels of EGFP-M, EGFP-M(△264-313) and EGFP in DF-1 cells transfected with different doses of plasmid. DF-1 cells were transfected with the plasmid pEGFP-M, pEGFP-M(Δ264-313), or pEGFP-C1 at a dose of 1.0 μg, 2.0 μg or 4.0 μg. The expression levels of EGFP-M, EGFP-M(Δ264-313) and EGFP in plasmid-transfected cells were examined at 36 hpt. The relative expression levels of the indicated proteins to control GAPDH expression levels were determined by densitometry using ImageJ software version 1.8.0. D Transcription levels of the chBRD2 gene in DF-1 cells transfected with different doses of pEGFP-M, pEGFP-M(Δ264-313), or pEGFP-C1. The relative transcription levels of the chBRD2 gene were compared with those of the control GAPDH gene. Error bars represent standard deviations (mean ± SD) (**P < 0.01; ***P < 0.001 compared to the value of non-transfected cells).