Fig. 1From: Small molecules block the interaction between porcine reproductive and respiratory syndrome virus and CD163 receptor and the infection of pig cellsEstablishing BiFC Assays and Screening Compounds that Inhibit the PPI Between PRRSV and CD163. a Scheme diagram for the BiFC assay fusion protein constructs between Pig CD163 SRCRs or PRRSV minor envelope glycoproteins and the fragments of Venus protein VN155(I152L) or VC155), respectively. b Left: SRCR5-VN or SRCR2-VN plasmid was co-transfected with GP2a-VC to HEK293T cells, with fluorescent images taken at 24 h after transfection. Bar = 250 μm. Right: Cell fluorescence quantified by Fiji. Mean ± SD. n = 3. **: p < 0.01. c Left: SRCR5-VN or SRCR2-VN plasmid was co-transfected with GP4-VC to HEK293T cells, with fluorescent images taken at 24 h after transfection. Bar = 250 μm. Right: Relative fluorescence intensity quantified. Mean ± SD. n = 3. **: p < 0.01. d Chemical structure of compound B7. e Left: BiFC assay between SRCR5-VN and GP2a-VC proteins. Images showing positive inhibitory effect of compound B7 but not B8, with DMSO as the Ctrl. Bar = 250 μm; Right: Relative fluorescence intensity quantified. Mean ± SD, n = 3. f Left: BiFC assay between SRCR5-VN and GP4-VC proteins showing similar inhibitory effect by B7 compound but not by B8. Bar = 120 μm. Right: Relative fluorescence intensity quantified. Mean ± SD, n = 3Back to article page