Dai Jinling, Zhang Shengli, Bai Yu'e
College of Forestry, Inner Mongolia Agricultural University, Hohhot 010019, China.
Plants (Basel). 2025 Jul 11;14(14):2141. doi: 10.3390/plants14142141.
In the severe environment of Hunshandake Sandy Land, the uncommon and indigenous Chinese tree species is an important biological component. Conventional seed propagation in is constrained by low germination rates, prolonged breeding cycles, and hybrid offspring genetic instability, limiting efficient varietal improvement. In contrast, somatic embryogenesis (SE) offers superior propagation efficiency, exceptional germination synchrony, and strict genetic fidelity, enabling rapid mass production of elite regenerants. However, SE in is hampered by severe genotype dependence, poor mature embryo induction rates, and loss of embryogenic potential during long-term cultures, restricting the production of high-quality seedlings. In this study, we aimed to analyze the transcriptome and metabolome of three crucial phases of SE: mature somatic embryos (MSEs), globular somatic embryos (GSEs), and embryogenic calli (EC). Numerous differentially expressed genes (DEGs) were found, especially in pathways linked to ribosomal functions, flavonoid biosynthesis, and the metabolism of starch and sucrose. Additionally, 141 differentially accumulated metabolites (DAMs) belonging to flavonoids, organic acids, carbohydrates, lipids, amino acids, and other metabolites were identified. An integrated study of metabolomic and transcriptome data indicated considerable enrichment of DEGs and DAMs in starch and sucrose metabolism, as well as phenylpropanoid biosynthesis pathways, all of which are required for somatic embryo start and development. This study revealed a number of metabolites and genes linked with SE, offering important insights into the molecular mechanisms driving SE in and laying the groundwork for the development of an efficient SE system.
在浑善达克沙地的恶劣环境中，这种珍稀的本土树种是重要的生物组成部分。传统的种子繁殖受到发芽率低、育种周期长和杂交后代遗传不稳定的限制，阻碍了有效的品种改良。相比之下，体细胞胚胎发生（SE）具有更高的繁殖效率、出色的发芽同步性和严格的遗传保真度，能够快速大量生产优良再生植株。然而，该树种的体细胞胚胎发生受到严重的基因型依赖性、成熟胚诱导率低以及长期培养过程中胚胎发生潜力丧失的阻碍，限制了高质量苗木的生产。在本研究中，我们旨在分析体细胞胚胎发生三个关键阶段的转录组和代谢组：成熟体细胞胚（MSE）、球形体细胞胚（GSE）和胚性愈伤组织（EC）。发现了许多差异表达基因（DEG），特别是在与核糖体功能、黄酮类生物合成以及淀粉和蔗糖代谢相关的途径中。此外，还鉴定出141种差异积累代谢物（DAM），属于黄酮类、有机酸、碳水化合物、脂质、氨基酸和其他代谢物。代谢组学和转录组数据的综合研究表明，淀粉和蔗糖代谢以及苯丙烷生物合成途径中DEG和DAM显著富集，这些都是体细胞胚启动和发育所必需的。本研究揭示了许多与体细胞胚胎发生相关的代谢物和基因，为深入了解该树种体细胞胚胎发生的分子机制提供了重要见解，并为建立高效的体细胞胚胎发生系统奠定了基础。
