Fig. 2: GA signalling on the xylem side of the cambium is required to promote secondary xylem formation.
From: Gibberellins promote polar auxin transport to regulate stem cell fate decisions in cambium
a–d, Root cross-sections after a 6 day induction in 4-day-old seedlings of Col-0 (a) or with mutated RGAΔ17 expressed in the early phloem cell (pPEAR1:XVE»RGAΔ17) (b), the stem cells (pANT:XVE»RGAΔ17) (c) or the early xylem (pATHB8:XVE»RGAΔ17) (d). Black dotted lines indicate the most recent divisions. e, Quantification of the total xylem cell number (cells within the most recent cell divisions) in a–d. Scale bars, 20 µm (a–d). Significant differences based on a two-tailed Wilcoxon test are indicated. NS, not significant. Numbers in e indicate number of samples. The boxes in the box-and-whisker plots show the median and the interquartile range, and the whiskers show the total range. Individual data points are plotted as purple dots. p, phloem; x, xylem. All experiments were repeated three times.
