Fig. 2: PtrVCS2 regulates vascular cambium proliferation in P. trichocarpa.
a, Phenotypes of the WT and OE-PtrVCS2 #3 transgenics. The inset shows a magnification of an OE-PtrVCS2 #3 transgenic plant. Scale bars, 10 cm. b, Basal stems of the WT and OE-PtrVCS2 #3 transgenics. Scale bar, 1 mm. c, Histochemistry and histological analysis of the WT and OE-PtrVCS2 #3 transgenics. d, Number of cambium cell layers in stem vascular tissues of the WT and OE-PtrVCS2 #3 transgenics. e, Phenotypes of the WT and the ptrvcs2 and ptrvcs2 ptrvcs2-h mutants. Scale bar, 10 cm. f, Basal stems of the WT and the ptrvcs2 #1 and ptrvcs2 ptrvcs2-h #1 mutants. Scale bar, 1 mm. g, Histochemistry and histological analysis of the WT and ptrvcs2 ptrvcs2-h #1 mutants. h, Number of cambium cell layers in stem vascular tissues of the WT and ptrvcs2 ptrvcs2-h #1 mutants. In c and g, the cross-sections were stained with toluidine blue O. Scale bars, 25 µm. The black brackets mark the cambium cells in one radial cell file. The insets show close-ups of cambium cells (green), adjacent phloem cells (blue) and adjacent xylem cells (yellow). In d and h, the number of cambium cell layers of at least ten radial cell files was counted within one cross-section from each biological replicate. Three biological replicates were analysed. n = 30 for d; n for h is shown in the panel. The boxes show the median and the upper and lower quantiles, and the whiskers represent the data range excluding outliers. Two-tailed Student’s t-test: **P < 0.01; ***P < 0.001. The P values versus the WT control for the OE-PtrVCS2 #3 transgenics in d are as follows: 5th, 0.0025; 6th, <0.0001; 7th, <0.0001; 8th, <0.0001; 10th, <0.0001; 12th, <0.0001; 14th, <0.0001; 16th, <0.0001; 18th, <0.0001; 20th, <0.0001. The P values versus the WT control for the ptrvcs2 ptrvcs2-h #1 mutants in h are as follows: 5th, <0.0001; 6th, <0.0001; 7th, <0.0001; 8th, <0.0001.
