Table4_Transcriptome and metabolome profiling unveil the accumulation of chlorogenic acid in autooctoploid Gongju.xlsx

BackgroundGongju is recognized as one of the four traditional Chinese medicinal herbs, and its main constituents are chlorogenic acid (CGA) and its derivative material. CGA content in autooctoploid Gongju are considerably elevated compared with those in parental tetraploid Gongju at different flowering stages. However, the underlying molecular mechanisms governing the regulation CGA content remain poorly understood.MethodsTherefore, we conducted integrated transcriptome and metabolome analyses of different flowering stages in autooctoploid and tetraploid Gongju to elucidate the underlying molecular mechanisms governing CGA biosynthesis.ResultsTranscriptome analysis showed that the number of differentially expressed genes in the budding stage (BS), early flowering stage (EF), and full flowering stage (FF) of tetraploid and octoploid Gongju were 3859, 11,211, and 6837, respectively. A total of 563, 466, and 394 differential accumulated metabolites were respectively identified between the bud stages of tetraploid and octoploid Gongju (4BS vs. 8BS), between the early flowering stages of tetraploid and octoploid Gongju (4EF vs. 8EF), and the full flowering stages of tetraploid and octoploid Gongju (4FF vs. 8FF) groups. The integrated analysis of transcriptomics and metabolomics revealed that the expression of pma6460 and mws0178, which are key enzymes involved in the CGA synthesis pathway, increased during the flowering stages of octoploid Gongju relative to that of tetraploid Gongju. The expression levels of CmHQT and CmC3H genes associated with CGA synthesis were higher in octoploid plants than in tetraploid plants at various flowering stages. To investigate the potential regulation of transcription factors involved in CGA synthesis, we analyzed the coexpression of CmC3H and CmHQT with CmMYBs and CmbHLHs. Results indicated that transcription factors, such as CmMYB12 (Cluster-30519.0), CmMYB26 (Cluster-75874.0), CmMYB5 (Cluster-94106.0), CmMYB1 (Cluster-71968.7), CmbHLH62 (Cluster-32024.1), CmbHLH75 (Cluster-62341.0), CmbHLH62 (Cluster-32024.8), CmbHLH75 (Cluster-60210.0), and CmbHLH16 (Cluster-90665.1) play a pivotal role in CGA synthesis regulation. The present study provides novel insights into the molecular mechanisms underlying CGA accumulation in autopolyploid Gongju.

背景：背景姜（Gongju）被誉为我国四大传统中药材之一，其主要成分包括氯原酸（CGA）及其衍生物。相较于亲本四倍体姜，自二倍体姜在各个开花阶段中的CGA含量显著提高。然而，调控CGA含量背后的分子机制尚不清楚。方法：因此，本研究对自二倍体和四倍体姜在不同开花阶段进行了转录组与代谢组学的综合分析，以阐明CGA生物合成的分子机制。结果：转录组分析表明，四倍体和八倍体姜在萌芽期（BS）、早期开花期（EF）和完全开花期（FF）中差异表达基因的数量分别为3859、11,211和6837。分别在四倍体和八倍体姜的芽阶段（4BS vs. 8BS）、早期开花阶段（4EF vs. 8EF）以及完全开花阶段（4FF vs. 8FF）组中，分别鉴定出563、466和394种差异积累的代谢物。转录组与代谢组学的综合分析揭示了在八倍体姜的花开阶段，CGA合成途径中的关键酶pma6460和mws0178的表达量相较于四倍体姜有所增加。与CGA合成相关的CmHQT和CmC3H基因在八倍体植物中的表达水平高于四倍体植物，且在各个开花阶段均如此。为了探究参与CGA合成的转录因子的潜在调控作用，我们分析了CmC3H和CmHQT与CmMYBs和CmbHLHs的共表达。结果表明，转录因子如CmMYB12（Cluster-30519.0）、CmMYB26（Cluster-75874.0）、CmMYB5（Cluster-94106.0）、CmMYB1（Cluster-71968.7）、CmbHLH62（Cluster-32024.1）、CmbHLH75（Cluster-62341.0）、CmbHLH62（Cluster-32024.8）、CmbHLH75（Cluster-60210.0）和CmbHLH16（Cluster-90665.1）在CGA合成的调控中扮演着至关重要的角色。本研究为自二倍体姜中CGA积累的分子机制提供了新的见解。