FIGURE 6.

Changes in cell morphology induced by EXO70C2 are controlled by its phosphorylation status. Tobacco pollen tubes were transiently transformed with YFP:AtEXO70C2 wild type (WT), phospho-dead (PD), and phospho-mimetic (PM) variants and imaged 8 h after transformation by spinning disk confocal microscopy. Cells expressing YFP:GUS and Arabidopsis YFP:EXO70A2 were used for comparison. Left, frequencies of pollen tubes exhibiting normal or abnormal morphology (abberant cell shape, membrane invaginations). At least 61 cells per variant were imaged in three independent experiments. Different letters indicate significant differences between samples at P < 0.05. Right, typical images displayed using a color intensity code with the same pixel range set for all images (i.e., reflecting differences in protein expression levels). Bar 10 μm.