Confocal imaging of N. tabacum pollen tubes co-expressing Rab11DN with GFP-SYP124. Scale bars = 20 μm. A and B: Optical section of pollen tubes with disturbed apical morphology due to Rab11DN over-expression. Along with a partial loss of polarity, the cells exhibit high protein localization in the flanks and apical plasma membrane and almost complete dissipation of the apical vesicle labelling. C: Distribution of average fluorescence intensity along the first 40 μm of the pollen tubes plasma membrane (n = 10) as depicted in the diagram. The distribution is statistically different (P = 2E-18) from GFP-SYP124 alone (compare with figure 1F). Error bars not displayed for the sake of clarity. D: Optical section of a depolarized pollen tube due to Rab11DN over-expression. SYP124 distribution is uniform in the swollen apex. Along with high protein localization in the flanks and apical plasma membrane, labelling of large endomembrane-like structures is visible.