Open Access

ARTICLE

Trilobatin Acts as a Marker Metabolite Involved in Flavonoid Accumulation Regulated by CsWRKY28-MYC2 with Trypsin Activation in Cucumber (Cucumis sativus)

Enyan Chen^1,#, Jingyu Jia^1,3,#, Jiaju Sun¹, Jie Wang², Xinxin Chen¹, Xin Li^1,3,4,*

1 College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, 471023, China
2 Chinese Academy of Agricultural Sciences Cotton Research Institute, Anyang, 455000, China
3 The National and Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology of Characteristic Fruit Trees in South Xinjiang, Tarim University, Alar, 843300, China
4 National Demonstration Center for Experimental Food Processing and Safety Education, Luoyang, 471000, China

* Corresponding Author: Xin Li. Email:
# These authors contributed equally to this work

(This article belongs to the Special Issue: Influence of Biotic and Abiotic Stresses Signals on Plants and their Performance at Different Environments)

Phyton-International Journal of Experimental Botany 2024, 93(11), 2837-2856. https://doi.org/10.32604/phyton.2024.057932

Received 31 August 2024; Accepted 18 October 2024; Issue published 30 November 2024

Abstract

During post-harvest storage of Cucumis sativus fruit, the application of trypsin treatment could increase flavonoid compound levels and reduce oxidative damage. To investigate the mechanism of trypsin-induced flavonoid biosynthesis in C. sativus, we conducted a combined analysis of transcriptomics and widely targeted metabolomics. One hundred and seventy-five significantly different metabolites were obtained from metabolomics data. The kyoto encyclopedia of genes and genomes (KEGG) functional enrichment results indicated that these metabolites were mainly involved in the phenylpropanoid biosynthesis pathway. By combining the results of the weighted gene co-expression network analysis (WGCNA) with the 130 upregulated phenylpropanoid metabolites, 22 significantly upregulated phenylpropanoid metabolites were identified. Trilobatin was identified as the most prominent metabolite through cluster analysis and variable importance in projection (VIP) analysis. High performance liquid chromatography (HPLC) experiments confirmed that trilobatin was the key metabolite induced by trypsin. The transcriptomic results showed that 1068 genes in the brown module of WGCNA were highly positively correlated with flavonoid biosynthesis. The gene set enrichment analysis (GSEA) identified leading edges in 4 key KEGG pathways. Finally, combined with WGCNA and GSEA analysis results, 35 core genes were obtained. The co-expression network of transcriptomics and metabolomics suggested that CsWRKY28 and CsMYC2 regulated the biosynthesis of trilobatin. The quantitative real-time polymerase chain reaction (RT-qPCR) and dual luciferase experiments confirmed the activation effect of CsWRKY28 on CsMYC2 and downstream target genes. This study revealed the key transcription factors involved in the trypsin-controlled biosynthesis of trilobatin in C. sativus and provided a new theoretical basis for elucidating the molecular mechanism of trypsin preservation.

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Keywords

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Supplementary Material

Supplementary Material File

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