Abstract: To investigate the molecular mechanisms of associated genes and metabolic pathways during leaf senescence of Medicago truncatula, we took mature leaves and senescence leaves of three different developmental stages of Medicago truncatula as plant materials. Through transcriptome sequencing, the transcriptome differences between all samples were compared. Compared with mature leaves, 2 990 differentially expressed genes were identified, exhibiting differentially expressed in all three senescent samples, of which a total of 2 684 (89.77%) differentially expressed genes was function annotated. The reliability of high-throughput sequencing was also confirmed by quantitative real-time PCR (qRT-PCR) method. Further analysis revealed that the differentially expressed genes were involved in 33 families of higher plant transcription factors, including ERF, WRKY, bHLH, MYB, NAC and bZIP. In addition, 837 genes associated with leaf senescence were identified. In this study, a large number of differentially expressed genes were discovered during leaf senescence in Medicago truncatula, which provided a reference for further analysis the regulatory mechanisms of leaf development and senescence in Medicago truncatula.

Key words: Medicago truncatula, Leaf senescence, Ttranscriptome sequencing, Functional annotation

摘要： 为探究蒺藜苜蓿（Medicago truncatula）叶片衰老过程中相关基因的分子机制及代谢通路，本研究以其成熟叶片和衰老初期、中期、末期叶片为研究对象。通过转录组测序，比较4个发育阶段样品之间的转录组差异。结果表明，与成熟叶片相比，共筛选出2 990个差异表达基因（DEGs），在所有衰老样本中表达水平均发生显著变化，其中有2 684条（89.77%）可进行基因功能注释；同时利用实时荧光定量PCR（qRT-PCR）结果证实了转录组测序的可靠性。进一步分析发现，DEGs涉及高等植物转录因子33个家族，包括ERF、WRKY、bHLH、MYB、NAC和bZIP。此外，还发现了837个与叶片衰老相关的基因。本研究发现了蒺藜苜蓿叶片衰老过程中大量差异表达的基因，为进一步分析蒺藜苜蓿叶片发育和衰老的调控机制提供参考。

关键词: 蒺藜苜蓿, 叶片衰老, 转录组测序, 功能注释