title: Transcriptional control of flavonoid biosynthesis: fine-tuning of the MYB-bHLH-WD40 (MBW) complex.
abstract: Flavonoids are plant secondary polyphenolic metabolites and fulfil many vital biological functions, offering a valuable metabolic and genetic model for studying transcriptional control of gene expression. Arabidopsis thaliana mainly accumulates 3 types of flavonoids, including flavonols, anthocyanins, and proanthocyanidins (PAs). Flavonoid biosynthesis involves a multitude of well-characterized enzymatic and regulatory proteins. Three R2R3-MYB proteins (MYB11, MYB12, and MYB111) control flavonol biosynthesis via activating the early biosynthetic steps, whereas the production of anthocyanins and PAs requires the MYB-bHLH-WD40 (MBW) complex to activate the late biosynthetic genes. Additional regulators of flavonoid biosynthesis have recently come to light, which interact with R2R3-MYBs or bHLHs to organize or disrupt the formation of the MBW complex, leading to enhanced or compromised flavonoid production. This mini-review gives an overview of how these novel players modulate flavonoid metabolism and thus plant developmental processes and further proposes a fine-tuning mechanism to complete the complex regulatory network controlling flavonoid biosynthesis.
authors.affiliation: Department of Botany; Osnabrück University; 49076, Osnabrück, Germany.
authors.forename: Shutian
authors.initials: S
authors.lastname: Li
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D005419:Flavonoids / Q000096:biosynthesis*; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D012639:Seeds / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D005419:Flavonoids; D007210:Indoleacetic Acids; D014157:Transcription Factors
keywords: Arabidopsis thaliania; MBW complexes; MYBL2; SPL9; TCP3; TT1; flavonoids