Network of the CAD gene Sobic.004G071000. (A) The CAD network. The query gene Sobic.004G071000 is highlighted by yellow, the blue line represents the negative co-expression of the conjoined gene, the orange line represents the positive co-expression of the conjoined gene, and the purple line indicates that the two nodes have a PPI relationship. The pink rhombus represents TFs. Here, one is MYB and the other is bHLH. The purple rectangles represent the carbohydrate-active enzyme family. The dark yellow hexagonal gene participated in phenylpropanoid biosynthesis pathway. (B) The transcriptome analysis of all of the CAD co-expression network genes. We selected the genotype type of PI455230 and different tissue, such as seed and leaf, and used cluster 3.0 software to illustrate the expression profile. We also highlighted the important genes of the network with the same colors as in Figure 3A. (C) The lignin pathway illustrates the biosynthesis process of the three kinds of lignin monomers, S-, G- and H-lignin. In the pathway, the related regulation factors, as found in published papers, are labeled with arrows. The up arrows represent up-regulation, while the down arrows represent down-regulation.