Characterization of the Brassica napus Flavonol Synthase Gene Family Reveals Bifunctional Flavonol Synthases
- PMID: 34721462
- PMCID: PMC8548573
- DOI: 10.3389/fpls.2021.733762
Characterization of the Brassica napus Flavonol Synthase Gene Family Reveals Bifunctional Flavonol Synthases
Abstract
Flavonol synthase (FLS) is a key enzyme for the formation of flavonols, which are a subclass of the flavonoids. FLS catalyzes the conversion of dihydroflavonols to flavonols. The enzyme belongs to the 2-oxoglutarate-dependent dioxygenases (2-ODD) superfamily. We characterized the FLS gene family of Brassica napus that covers 13 genes, based on the genome sequence of the B. napus cultivar Express 617. The goal was to unravel which BnaFLS genes are relevant for seed flavonol accumulation in the amphidiploid species B. napus. Two BnaFLS1 homeologs were identified and shown to encode bifunctional enzymes. Both exhibit FLS activity as well as flavanone 3-hydroxylase (F3H) activity, which was demonstrated in vivo and in planta. BnaFLS1-1 and -2 are capable of converting flavanones into dihydroflavonols and further into flavonols. Analysis of spatio-temporal transcription patterns revealed similar expression profiles of BnaFLS1 genes. Both are mainly expressed in reproductive organs and co-expressed with the genes encoding early steps of flavonoid biosynthesis. Our results provide novel insights into flavonol biosynthesis in B. napus and contribute information for breeding targets with the aim to modify the flavonol content in rapeseed.
Keywords: 2-oxoglutarate-dependent dioxygenases; bifunctionality; flavanone 3-hydroxylase; flavonoid biosynthesis; gene family; rapeseed; specialized metabolism.
Copyright © 2021 Schilbert, Schöne, Baier, Busche, Viehöver, Weisshaar and Holtgräwe.
Conflict of interest statement
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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References
-
- Andrews S. (2018). FastQC, a quality control tool for high throughput sequence data. Available online at: http://www.bioinformatics.babraham.ac.uk/projects/fastqc/ (accessed October 6, 2018)
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