Fig 7. CEP2 loss of function results in shortening the cell length and cell width of the longest trichoblasts (double arrows) in the root elongation zone at the level of the transition from the rapid elongation zone to the late elongation zone.

The residual CEP2 activity in cep1 cep2 double ko/kd mutants (cep1+cep2-RNAi) results in prolonged trichoblasts as compared to cep2 ko mutant plants, but shorter as compared to trichoblasts in WT plants. (A) 7 days old seedlings of WT, cep2 ko and cep1 cep2 double ko/kd plants were stained with propidium iodide and analyzed by CLSM (single pictures, 200-fold magnification). Two examples of propidium iodide stained roots are presented for each genotype. (B) Comparison of the trichoblast cell length (left) and the width (right) in 7 days old seedlings of WT plants with cep2 ko and cep1 cep2 double ko/kd mutants (cep1+cep2-RNAi; lines 2.21 and 3.14). Columns are marked with different letters indicating statistically different groups for the trichobalst cell length or with similar letters indicating groups not statistically different for trichoblast cell width according to the ANOVA-and Duncan test (p<0.001). (C) Trichoblast cell length expressed as percentage of WT plants. Data represent the respective means of two independent experiments (biological replica) comprising 8 and 9 seedlings per line, respectively, with three trichoblast cells evaluated per seedling.