RRC ID 4807
Author Stracke R, De Vos RC, Bartelniewoehner L, Ishihara H, Sagasser M, Martens S, Weisshaar B.
Title Metabolomic and genetic analyses of flavonol synthesis in Arabidopsis thaliana support the in vivo involvement of leucoanthocyanidin dioxygenase.
Journal Planta
Abstract Flavonol synthase (FLS) (EC-number, the enzyme that catalyses the conversion of flavonols into dihydroflavonols, is part of the flavonoid biosynthesis pathway. In Arabidopsis thaliana, this activity is thought to be encoded by several loci. In addition to the FLAVONOL SYNTHASE1 (FLS1) locus that has been confirmed by enzyme activity assays, loci displaying similarity of the deduced amino acid sequences to FLS1 have been identified. We studied the putative A. thaliana FLS gene family using a combination of genetic and metabolite analysis approaches. Although several of the FLS gene family members are expressed, only FLS1 appeared to influence flavonoid biosynthesis. Seedlings of an A. thaliana fls1 null mutant (fls1-2) show enhanced anthocyanin levels, drastic reduction in flavonol glycoside content and concomitant accumulation of glycosylated forms of dihydroflavonols, the substrate of the FLS reaction. By using a leucoanthocyanidin dioxygenase (ldox) fls1-2 double mutant, we present evidence that the remaining flavonol glycosides found in the fls1-2 mutant are synthesized in planta by the FLS-like side activity of the LDOX enzyme.
Volume 229(2)
Pages 427-45
Published 2009-1
DOI 10.1007/s00425-008-0841-y
PMID 18998159
MeSH Alleles Anthocyanins / metabolism Arabidopsis / enzymology* Arabidopsis / genetics* Arabidopsis / metabolism Flavonols / biosynthesis* Flavonols / chemistry Gene Expression Regulation, Plant Genes, Plant Metabolomics* Molecular Sequence Data Multigene Family Mutation / genetics Oxygenases / genetics Oxygenases / metabolism* Promoter Regions, Genetic / genetics Seedlings / enzymology Seedlings / metabolism Transcription Factors / metabolism
IF 3.249
Times Cited 46
Arabidopsis / Cultured plant cells, genes pst16145