Figure 8

BiFC experiments showing that CrSGD fused either in N-terminus or C-terminus of YFP fragments are able to specifically interact. To evaluate the BiFC, undifferentiated C. roseus cells were co-transformed with the construct indicated on the left (fusions with the YFP^C fragment) and the construct indicated on the top (fusions with the YFP^N fragment). Interactions between two CrSGD fusions allowed reconstitution of the YFP fluorochrome with a diffuse nuclear fluorescence pattern when at least one of the C-terminus was blocked by a YFP fragment (e, f, h), whereas an aggregated fluorescence pattern required the interaction of two fusion proteins with an accessible CrSGD C-terminal extremity. bZIP63 was used as a positive control of BiFC and to test for non-specific interaction with CrSGD fusions. The efficiency of the co-transformation was further evaluated with the co-transformation of a "plastid"-CFP marker (Additional file 4). The images presented are merges of the YFP BiFC channel (Magenta false colour) and DIC channel to show the morphology of the cells. YFP^N, (aa 1-173); YFP^C, (aa 156-239). Bar: 10 μm.