Figure 3.

Estimation of the G2 Phase Length along the Root Meristem.

(A) Epidermal cell layer of a root labeled with EdU (15 min) and analyzed after a 4 h and 15 min chase. EdU was detected (red) and all nuclei stained with DAPI (blue). The inset contains an enlarged image of the box in the left panel to highlight the presence of EdU-positive (yellow arrowheads) and -negative (white arrowheads) metaphase nuclei.

(B) Distribution of EdU-labeled (red) and unlabeled (blue) mitotic figures along individual epidermal cell files at different chase times after a 15-min EdU pulse. The relative position within the RAM was determined as in Figure 2. Statistical analysis of the distributions was performed with the Wilcoxon-Mann-Whitney test, as indicated: **P < 0.01 and ***P < 0.005.

(C) Kinetics of appearance of EdU-labeled mitotic figures in two regions of the RAM at different chase times after a 15-min pulse with EdU: between positions −0.2 and −0.6 (cells undergoing their last cell cycle; circles) and between positions −0.6 and −1.0 (cells in previous cell cycles; squares).

(D) Distribution of EdU-labeled (red) and unlabeled (blue) mitotic figures in the wild type (filled circles) and htr1,2,3,9 quadruple mutant (circles). The analysis was performed as in (B). The EdU-labeled cell distributions (Col-0 versus htr1,2,3,9 mutant) were not significantly different based on the Wilcoxon-Mann-Whitney test (P < 0.05).