Transcriptomic and free monoterpene analyses of aroma reveal that isopentenyl diphosphate isomerase inhibits monoterpene biosynthesis in grape (Vitis vinifera L.)

• Published in: BMC plant biology 2024-06, Vol.24 (1), p.595-15, Article 595
• Main Authors: Chen, Tianchi, Xu, Tao, Wang, Jinnan, Zhang, Tianye, Yang, Jin, Feng, Lixiao, Song, Tiefeng, Yang, Jian, Wu, Yueyan
• Format: Article
• Language: English
• Subjects: Amino acid sequence; Amino acids; Aroma; Aroma compounds; Aromatic compounds; Berries; Biosynthesis; Botanical research; Carbon-Carbon Double Bond Isomerases - genetics; Carbon-Carbon Double Bond Isomerases - metabolism; Chemical properties; Chloroplasts; Coding; Cultivars; D-Xylulose 5-phosphate; DNA binding proteins; Flavor compounds; Fruits; Functional analysis; Gas chromatography; Gas Chromatography-Mass Spectrometry; GC-MS; Gene expression; Gene Expression Regulation, Plant; Genes; Genetic aspects; Genetic engineering; Genetic transcription; Grape; Grapes; Hemiterpenes; Information processing; Isomerases; Isopentenyl diphosphate; Kinases; Linalool; Mass spectrometry; Mass spectroscopy; Metabolism; Mevalonate kinase; Monosaccharides; Monoterpene biosynthesis; Monoterpenes; Monoterpenes - metabolism; N-Terminus; Odorants; Phosphates; Physiological aspects; Plant Proteins - genetics; Plant Proteins - metabolism; Protein biosynthesis; Reductases; Regulatory mechanisms (biology); Regulatory sequences; RNA sequencing; RNA-Seq; Scientific equipment and supplies industry; Signal transduction; Sugars; Terpineol; Transcription factors; Transcriptome; Transcriptomics; Vitaceae; Vitis - enzymology; Vitis - genetics; Vitis - metabolism; Vitis vinifera; Wines; Xylulose
• ISSN: 1471-2229; 1471-2229
• DOI: 10.1186/s12870-024-05306-y

Monoterpenes are among the most important volatile aromatic compounds contributing to the flavor and aroma of grapes and wine. However, the molecular basis of monoterpene biosynthesis has not yet been fully elucidated. In our study, transcriptomics and gas chromatography-mass spectrometry (GC-MS) were used to mine candidate genes and transcription factors involved in monoterpene biosynthesis between high-monoterpene and zero-monoterpene table grape cultivars. We found that monoterpene biosynthesis was positively correlated by the expression of five genes encoding 1-deoxy-D-xylulose-5-phosphate synthase (VvDXSs), one encoding 4-hydroxy-3-methylbut-2-enyl diphosphate reductase (VvHDR), three hydroxy-3-methylglutaryl-CoA synthases (VvHMGSs) and one mevalonate kinase (VvMVK), whereas the expression of one isopentenyl diphosphate isomerase (VvIDI) and one 3-hydroxy-3-methylglutaryl-CoA reductase (VvHMGR) negatively correlated monoterpene biosynthesis. Of these genes, VvIDI was selected to validate its function in monoterpene accumulation through a transient overexpression experiment, and was shown to inhibit the biosynthesis of grape linalool and α-terpineol. Meanwhile, we found that a 64-amino acid extension sequence at the N-terminus can guide the VvIDI protein to target the chloroplast. The findings of this study should help to guide future functional analysis of key genes as well as mining the potential regulatory mechanism of monoterpene biosynthesis in grapes and grape products.