多花黄精种子解除休眠和萌发的代谢产物变化机制

Changes of Metabolites in Dormancy Release and Germination of Polygonatum cyrtonema Seeds

摘要:

多花黄精(Polygonatum cyrtonema)种子存在综合性休眠，严重制约其生产和产业发展。该研究利用暖温沙藏处理打破种子休眠，并以休眠解除和萌发过程的6个阶段为研究对象，进行代谢组学、转录组学以及二者的联合分析。结果表明，氨基酸代谢与合成在多花黄精种子解除休眠和萌发过程中发挥关键作用；联合分析氨基酸代谢与合成相关通路中l-苏氨酸、l-谷氨酸、吲哚、S-腺苷甲硫氨酸和胆碱5个代谢物及10个差异基因的相关性；挖掘了二磷酸腺苷、丙氨酸-色氨酸、香豆素151、女贞苷、N-甲基苏氨酸和景天庚酮糖-7-磷酸作为多花黄精种子萌发的重要特征分子以及与它们相关的10个基因，并通过qPCR验证了部分基因的表达趋势。该研究从代谢物变化和分子机制层面揭示了多花黄精种子休眠解除的关键代谢通路和基因调控网络，为进一步解析种子休眠解除的分子机制和优化多花黄精种子萌发条件提供了理论依据。

Abstract:

The seeds of Polygonatum cyrtonema have a comprehensive dormancy, which seriously restricts its production and industrial development. The seed dormancy was broken by using warm sand storage treatment, and the changes in metabolomics, transcriptomics at six stages of dormancy release and germination were analyzed. The results showed that amino acid metabolism and synthesis played a key role in the process of dormancy release and germination of P. cyrtonema seeds. The correlation between five metabolites (l-threonine, l-glutamic acid, indole, S-adenosylmethionine and choline) and ten differentially expressed genes in the amino acid metabolism and synthesis related pathways was analyzed. Adenosine diphosphate, alanine-tryptophan, coumarin 151, loniceroside, N-methylthreonine and sedoheptulose-7-phosphate were identified as important characteristic molecules for the germination of P. cyrtonema seeds, and ten related genes were also identified. The expression trends of some genes were verified by qPCR. The key metabolic pathways and gene regulatory networks were revealed for the release of seed dormancy of P. cyrtonema from the levels of metabolite changes and molecular mechanisms, which would provide a theoretical basis for further understanding the molecular mechanism of seed dormancy release and optimizing the germination conditions of P. cyrtonema seeds.