Fig. 4.

All pairwise combinations for CYDV-encoded proteins, except L, were assayed in bimolecular fluorescence complementation experiments. Specific combinations are listed on the left-hand side of each column of single-plane confocal micrographs that show the location of YFP fluorescence (BiFC) relative to that of the CFP-marked nucleus (CFP). Interaction assays were conducted in leaf epidermal cells of transgenic N. benthamiana expressing CFP fused to the nuclear marker protein Histone 2B. The merger of the BiFC and CFP channels is also shown (Overlay). Protein fusions to each half of YFP were tested in all pairwise interactions, of which only a subset is shown here. Glutathione-S-transferase (GST) was used as a non-binding control. The majority of BiFC-negative results are not shown, save those necessary to confirm specificity of binding in the positive assays. Scale bar, 10 µm.