Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Center for Genomics and Biotechnology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Pingtan Science and Technology Research Institute, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Int J Mol Sci. 2023 Oct 12;24(20):15103. doi: 10.3390/ijms242015103.
Chinese fir ( (Lamb.) Hook.) stands as one of the pivotal afforestation tree species and timber resources in southern China. Nevertheless, the occurrence of seed abortion and a notably high proportion of astringent seeds significantly curtail the yield and quality of elite seeds, resulting in substantial economic losses. The development of astringent seeds is accompanied by significant physiological and biochemical alterations. Here, the first combined lipidomic and metabolomic analysis was performed to gain a comprehensive understanding of astringent seed traits. A total of 744 metabolites and 616 lipids were detected, of which 489 differential metabolites and 101 differential lipids were identified. In astringent seeds, most flavonoids and tannins, as well as proline and γ-aminobutyric acid, were more accumulated, along with a notable decrease in lipid unsaturation, indicating oxidative stress in the cells of astringent seeds. Conversely, numerous elemental metabolites were less accumulated, including amino acids and their derivatives, saccharides and alcohols, organic acids and nucleotides and their derivatives. Meanwhile, most lipid subclasses, mainly associated with energy storage (triglyceride and diglyceride) and cell membrane composition (phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine), also exhibited significant reductions. These results reflected a disruption in the cellular system or the occurrence of cell death, causing a reduction in viable cells within astringent seeds. Furthermore, only one lipid subclass, sphingosine phosphate (SoP), was more accumulated in astringent seeds. Additionally, lower accumulation of indole-3-acetic acid and more accumulation of salicylic acid (SA) were also identified in astringent seeds. Both SA and SoP were closely associated with the promotion of programmed cell death in astringent seeds. Collectively, our study revealed significant abnormal changes in phytohormones, lipids and various metabolites in astringent seeds, allowing us to propose a model for the development of astringent seeds in Chinese fir based on existing research and our findings. This work enriches our comprehension of astringent seeds and presents valuable bioindicators for the identification of astringent seeds.
杉木（(Lamb.) Hook.）是中国南方重要的造林树种和木材资源之一。然而，种子败育和高比例的涩籽现象严重降低了优质种子的产量和质量，造成了巨大的经济损失。涩籽的形成伴随着显著的生理生化变化。在这里，我们首次进行了联合脂质组学和代谢组学分析，以全面了解涩籽的特性。共检测到 744 种代谢物和 616 种脂质，其中鉴定出 489 种差异代谢物和 101 种差异脂质。在涩籽中，大多数类黄酮和单宁、脯氨酸和γ-氨基丁酸积累更多，而脂质不饱和程度显著降低，表明涩籽细胞发生氧化应激。相反，许多元素代谢物积累较少，包括氨基酸及其衍生物、糖和醇、有机酸和核苷酸及其衍生物。同时，大多数脂质亚类，主要与能量储存（甘油三酯和二酯）和细胞膜组成（磷脂酸、磷脂酰胆碱、磷脂酰乙醇胺）也显著减少。这些结果反映了细胞系统的破坏或细胞死亡的发生，导致涩籽中存活细胞的减少。此外，只有一种脂质亚类，即神经鞘氨醇磷酸（SoP）在涩籽中积累更多。此外，在涩籽中还发现吲哚-3-乙酸积累较少，水杨酸（SA）积累较多。SA 和 SoP 都与涩籽中程序性细胞死亡的促进密切相关。总的来说，我们的研究揭示了涩籽中植物激素、脂质和各种代谢物的显著异常变化，使我们能够根据现有研究和我们的发现，提出杉木涩籽发育的模型。这项工作丰富了我们对涩籽的理解，并为涩籽的鉴定提供了有价值的生物标志物。
