Integrated Metabolome and Transcriptome Analysis Unveils Novel Pathway Involved in the Formation of Yellow Peel in Cucumber
Open Access
- 2 February 2021
- journal article
- research article
- Published by MDPI AG in International Journal of Molecular Sciences
- Vol. 22 (3), 1494
- https://doi.org/10.3390/ijms22031494
Abstract
Yellow peel will adversely affect the appearance quality of cucumber fruit, but the metabolites and the molecular mechanism of pigment accumulation in cucumber peel remain unclear. Flavonoid metabolome and transcriptome analyses were carried out on the young peel and old peel of the color mutant L19 and the near-isogenic line L14. The results showed that there were 165 differential flavonoid metabolites in the old peel between L14 and L19. The total content of representative flavonoid metabolites in the old peel of L14 was 95 times that of L19, and 35 times that of young peel of L14, respectively. This might explain the difference of pigment accumulation in yellow peel. Furthermore, transcriptome analysis showed that there were 3396 and 1115 differentially expressed genes in the yellow color difference group (Young L14 vs. Old L14 and Old L14 vs. Old L19), respectively. These differentially expressed genes were significantly enriched in the MAPK signaling pathway–plant, plant–pathogen interaction, flavonoid biosynthesis and cutin, suberine and wax biosynthesis pathways. By analyzing the correlation between differential metabolites and differentially expressed genes, six candidate genes related to the synthesis of glycitein, kaempferol and homoeriodictyol are potentially important. In addition, four key transcription factors that belong to R2R3-MYB, bHLH51 and WRKY23 might be the major drivers of transcriptional changes in the peel between L14 and L19. Then, the expression patterns of these important genes were confirmed by qRT-PCR. These results suggested that the biosynthesis pathway of homoeriodictyol was a novel way to affect the yellowing of cucumber peel. Together, the results of this study provide a research basis for the biosynthesis and regulation of flavonoids in cucumber peel and form a significant step towards identifying the molecular mechanism of cucumber peel yellowing.Funding Information
- the Central Committee Guides Local Science and Technology Development Project of Hunan Province (2019XF5014, 2020CX18)
This publication has 82 references indexed in Scilit:
- Transcription factor WRKY23 assists auxin distribution patterns during Arabidopsis root development through local control on flavonol biosynthesisProceedings of the National Academy of Sciences of the United States of America, 2012
- Cucumber ( Cucumis sativus ) and melon ( C. melo ) have numerous wild relatives in Asia and Australia, and the sister species of melon is from AustraliaProceedings of the National Academy of Sciences of the United States of America, 2010
- Biochemical and Molecular Analysis of Pink Tomatoes: Deregulated Expression of the Gene Encoding Transcription Factor SlMYB12 Leads to Pink Tomato Fruit ColorPlant Physiology, 2009
- Structure and function of enzymes involved in the biosynthesis of phenylpropanoidsPlant Physiology and Biochemistry, 2008
- Flavonoid Accumulation in Arabidopsis Repressed in Lignin Synthesis Affects Auxin Transport and Plant GrowthTHE PLANT CELL ONLINE, 2007
- Flavanones in oranges, tangerines (mandarins), tangors, and tangelos: a compilation and review of the data from the analytical literatureJournal of Food Composition and Analysis, 2006
- Comprehensive identification of Arabidopsis thaliana MYB transcription factors interacting with R/B‐like BHLH proteinsThe Plant Journal, 2004
- Identification of the Enzymatic Active Site of Tobacco Caffeoyl-coenzyme A O-Methyltransferase by Site-directed MutagenesisOnline Journal of Public Health Informatics, 2001
- The regulation of transcription factor activity in plantsTrends in Plant Science, 1998
- Enzymatic synthesis of aromatic compounds in higher plants: Formation of naringenin (5,7,4′‐trihydroxyflavanone) from p‐coumaroyl coenzyme A and malonyl coenzyme AFEBS Letters, 1972