Protein-protein interaction studies in Tropaeolum majus tissue.
Leaves were infiltrated with Agrobacteria carrying constructs for the constitutive expression of MKK4 and MPK3, fused to the C- and N-terminal fragment of YFP, respectively. Bimolecular fluorescence complementation, documenting the interaction, was detected by UV microscopy, 5 dpi. top: UV image, bottom: bright-field image. For additional images see figure S1.