Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, P.O. Box 27, 00014, Helsinki, Finland.
State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an District, Hangzhou, 311300, Zhejiang, China.
Sci Rep. 2021 Feb 12;11(1):3778. doi: 10.1038/s41598-021-82848-3.
We studied the stress response of five-year-old Scots pine xylem to mechanical wounding using RNA sequencing. In general, we observed a bimodal response in pine xylem after wounding. Transcripts associated with water deficit stress, defence, and cell wall modification were induced at the earliest time point of three hours; at the same time, growth-related processes were down-regulated. A second temporal wave was triggered either at the middle and/or at the late time points (one and four days). Secondary metabolism, such as stilbene and lignan biosynthesis started one day after wounding. Scots pine synthesises the stilbenes pinosylvin and its monomethyl ether both as constitutive and induced defence compounds. Stilbene biosynthesis is induced by wounding, pathogens and UV stress, but is also developmentally regulated when heartwood is formed. Comparison of wounding responses to heartwood formation shows that many induced processes (in addition to stilbene biosynthesis) are similar and relate to defence or desiccation stress, but often specific transcripts are up-regulated in the developmental and wounding induced contexts. Pine resin biosynthesis was not induced in response to wounding, at least not during the first four days.
我们使用 RNA 测序研究了五年生苏格兰松树木质部对机械损伤的应激反应。总体而言，我们观察到松树木质部在受伤后呈现双峰反应。在最早的 3 小时时间点，与水分亏缺应激、防御和细胞壁修饰相关的转录本被诱导；与此同时，与生长相关的过程被下调。第二个时间波要么在中期和/或晚期（1 天和 4 天）触发。次生代谢物，如芪和木脂素生物合成在受伤后 1 天开始。苏格兰松树合成白藜芦醇及其单甲醚作为组成型和诱导型防御化合物。芪生物合成受创伤、病原体和 UV 胁迫诱导，但在形成心材时也受发育调控。将创伤反应与心材形成进行比较表明，许多诱导过程（除了芪生物合成外）相似，与防御或干燥胁迫有关，但在发育和创伤诱导的情况下，通常特定的转录本上调。松树树脂生物合成未因创伤而诱导，至少在前 4 天没有。
