Crystal Structure of Vaccinia Viral A27 Protein Reveals a Novel Structure Critical for Its Function and Complex Formation with A26 Protein
Figure 9
WRΔA27L, WR-A27-TM-N, WR-A27-TM-C, and WR-A27-6A induce cell-to-cell membrane fusion on L cells at neutral pH.
(A) L cells expressing GFP or RFP (1∶1 mixture) were either mock-infected or infected with WR, WRΔA27L, WR-A27R, WR-A27-TM-N, WR-A27-TM-C, and WR-A27-6A viruses at an MOI of 50 PFU/cell at 37°C for 30 min and monitored for cell-to-cell fusion at a neutral pH, as described in Materials and Methods. Cell images were photographed at 2 h post-infection. (B) Quantification of cell-to-cell fusion at neutral pH. The percentage of cells containing both GFP and RFP fluorescence was quantified as cell-cell fusion using Axio Vision Rel. 4.8 with a Zeiss Axiovert fluorescence microscope.