Comparative Metabolomic Analysis Reveals Distinct Flavonoid Biosynthesis Regulation for Leaf Color Development of Cymbidium sinense ‘Red Sun’

Abstract

The colorful leaf is an important ornamental character of Cymbidium sinense (C. sinense), especially the red leaf, which has always been attracted by breeders and consumers. However, little is documented on the formation mechanism of the red leaf of C. sinense. In this study, the changing patterns of flavonoid-related metabolites, corresponding enzyme activities and genes expression in the leaves of C. sinense ‘Red Sun’ from red to yellow and finally to green was investigated. A total of 196 flavonoid-related metabolites including 11 anthocyanins metabolites were identified using UPLC-MS/MS-based approach. In the process of leaf color change, 42 metabolites were identified as having significantly different contents and the content of 28 differential metabolites turned to zero. In anthocyanin biosynthetic pathway, content of all 15 identified metabolites showed downregulation trend in the process of leaf color change. Among the 15 metabolites, the contents of Naringenin chalcone, Pelargonidin O-acetylhexoside and Anthocyanin 3-O-beta-d-glucoside decreased to zero in the green leaf stage. The changing pattern of enzyme activity of 10 enzymes involved in the anthocyanin biosynthetic pathway showed different trends from red leaves that have turned yellow and finally green, while the expression of genes encoding these enzymes was all down-regulated in the process of leaf color change. The results of this study revealed the types of flavonoid-related metabolites and the comprehensive analysis of metabolites content, enzyme activities and genes expression providing a new reference for breeders to improve the leaf color of C. sinense ‘Red Sun’.

Integration of Transcriptome and Metabolome Provides New Insights to Flavonoids Biosynthesis in Dendrobium huoshanense

“…Subsequently, 4-Coumaric-CoA is converted to naringenin catalyzed by CHS and CHI. While naringenin is the key metabolite in flavonoid synthesis (Figure 6), catalyzed by different enzymes, the naringenin produces three branches, one branch produces flavonoid (eriodictyol, apigenin, and luteolin), the second branch produces flavonols (dihydrokaempferol, kaempferol, dihydroquercetin, and quercetin), and the third branch produces isoflavones, which is in agreement with the previous findings (Gao et al, 2020;Jiang et al, 2020). here have been reports that naringenin possesses a broad range of biological activities, such as anti-oxidant, hepatoprotective, anti-inflammatory, and anticarcinogenic effects (Raso et al, 2001), and the pharmacological potential of flavonoids in D. huoshanense needs to be further explored.…”

Molecular and Metabolic Insights into Anthocyanin Biosynthesis for Leaf Color Change in Chokecherry (Padus virginiana)

“…Two ANS genes ( Cluster-24837.114104 and Cluster-24837.114106 ) and one DFR genes ( Cluster-24837.115161 ) were significantly upregulated in PRL, which might result in the accumulation of colored anthocyanins in purple-red leaves. The UFGT gene can convert anthocyanins to a more stable water-soluble state as the last step of flavonoid pathway [ 31 ]. With high expression of two UFGT genes ( Cluster-24837.111509 and Cluster-24837.123865 ), the leaf color gradually turns purple-red, which is consistent with previous studies.…”

Analysis of metabolites in young and mature Docynia delavayi (Franch.) Schneid leaves using UPLC-ESI-MS/MS

“…The analysis of the sample extracts was performed using a UPLC-ESI-MS/MS system. It was performed by Metware Biotechnology Co., Ltd. (Wuhan, China) according to their standard procedures, as previously fully described by Gao et al (2020) . The difference was the UPLC gradient program, the flow rate and the injection volume.…”