School of Forestry and Resource Conservation, National Taiwan University, Taipei 10617, Taiwan.
Center for Systems Biology, National Taiwan University, Taipei 10617, Taiwan.
Int J Mol Sci. 2020 Jan 31;21(3):960. doi: 10.3390/ijms21030960.
Taiwania () is an important tree species in Taiwan because of the excellent properties of its wood and fascinating color qualities of its heartwood (HW), as well as the bioactive compounds therein. However, limited information is available as to the HW formation of this species. The objective of this research is to analyze the differentially expressed genes (DEGs) during the HW formation process from specific Taiwania xylem tissues, and to obtain genes that might be closely associated with this process. The results indicated that our analyses have captured DEGs representative to the HW formation process of Taiwania. DEGs related to the terpenoid biosynthesis pathway were all up-regulated in the transition zone (TZ) to support the biosynthesis and accumulation of terpenoids. Many DEGs related to lignin biosynthesis, and two DEGs related to pinoresinol reductase (PrR)/pinoresinol lariciresinol reductase (PLR), were up-regulated in TZ. These DEGs together are likely involved in providing the precursors for the subsequent lignan biosynthesis. Several transcription factor-, nuclease-, and protease-encoding DEGs were also highly expressed in TZ, and these DEGs might be involved in the regulation of secondary metabolite biosynthesis and the autolysis of the cellular components of ray parenchyma cells in TZ. These results provide further insights into the process of HW formation in Taiwania.
秃杉（）是台湾的一种重要树种，其木材性能优良，心材（HW）颜色鲜艳，具有生物活性化合物。然而，关于该树种 HW 形成的信息有限。本研究的目的是分析从特定的台湾杉木质部组织中 HW 形成过程中的差异表达基因（DEGs），并获得可能与该过程密切相关的基因。结果表明，我们的分析已经捕获了代表台湾杉 HW 形成过程的 DEGs。与萜类生物合成途径相关的 DEGs 在过渡区（TZ）中均上调，以支持萜类化合物的生物合成和积累。许多与木质素生物合成相关的 DEGs，以及两个与松脂醇还原酶（PrR）/枞木脂素-落叶松脂素还原酶（PLR）相关的 DEGs，在 TZ 中上调。这些 DEGs 可能共同参与为随后的木脂素生物合成提供前体。在 TZ 中还高度表达了几个转录因子、核酸酶和蛋白酶编码的 DEGs，这些 DEGs 可能参与调节次生代谢物生物合成和 TZ 中射线薄壁细胞的细胞成分的自溶。这些结果为台湾杉 HW 形成过程提供了更深入的了解。
