Fig. 5. Restricted lateral protein movement in the Arabidopsis shoot apex. Confocal images of GFP fluorescence for inflorescence meristems with surrounding young floral primordia from AG intron^*::NLS:2xGFP (A,D), AG intron^*::2xGFP (B,E) and AG intron^*::GLFY (C,F) plants. The confocal images have been overlaid with images from the transmitted-light channel for orientation only. Note that the confocal images are optical sections, which is not true for the transmitted-light images. The mutated AG sequences in the reporters activate expression in the shoot apical meristem and the center of young flowers. Close-up views of stage 3 flowers reveal discrete lateral boundaries of the GFP signal (D-F). No lateral movement is obvious in any of the three cases.