Fig. 3.

Changes in the expression of genes associated with cell division, cell expansion, and phytohormone signaling in the cambium of trees of different ages. In the heatmaps (A–C), the Left grid (red) shows the log₁₀ FPKM value of VC20, and the Right grid the log₂ (expression ratio) [log₂(VC200A/VC20_mean), log₂(VC200B/VC20_mean), log₂(VC200C/VC20_mean), log₂(VC600A/VC20_mean), log₂(VC600B/VC20_mean), log₂(VC600C/VC20_mean)]. (D) Expression ratios [log₂(VC200/VC20)] and [log₂(VC600/VC20)] of selected DEGs as determined by qRT-PCR and deep sequencing. Expression levels of genes related to (E) cell division, (F) IAA signaling, and (G) CTK signaling by qRT-PCR among more ages. The columns and error bars indicate the means and SDs (n = 3). The mean expression levels of these genes are from trees of four age groups (3 and 5 y, 5Y; 20 and 34 y, 20Y; 132, 152, 161, and 211 y, 200Y; and 538, 553, and 667 y, 600Y).