Differential combinatorial interactions of cis-acting elements recognized by R2R3-MYB, BZIP, and BHLH factors control light-responsive and tissue-specific activation of phenylpropanoid biosynthesis genes

Plant Mol Biol. 2005 Jan;57(2):155-71. doi: 10.1007/s11103-004-6910-0.

Abstract

Chalcone synthase (CHS), chalcone flavanone isomerase (CFI), flavanone 3-hydroxylase (F3H) and flavonol synthase (FLS) catalyze successive steps in the biosynthetic pathway leading to the production of flavonols. We show that in Arabidopsis thaliana all four corresponding genes are coordinately expressed in response to light, and are spatially coexpressed in siliques, flowers and leaves. Light regulatory units (LRUs) sufficient for light responsiveness were identified in all four promoters. Each unit consists of two necessary elements, namely a MYB-recognition element (MRE) and an ACGT-containing element (ACE). C1 and Sn, a R2R3-MYB and a BHLH factor, respectively, known to control tissue specific anthocyanin biosynthesis in Z. mays, were together able to activate the AtCHS promoter. This activation of the CHS promoter required an intact MRE and a newly identified sequence designated R response element (RREAtCHS) containing the BHLH factor consensus binding site CANNTG. The RRE was dispensable for light responsiveness, and the ACE was not necessary for activation by C1/Sn. These data suggest that a BHLH and a R2R3-MYB factor cooperate in directing tissue-specific production of flavonoids, while an ACE-binding factor, potentially a BZIP, and a R2R3-MYB factor work together in conferring light responsiveness.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyltransferases / genetics
  • Acyltransferases / metabolism
  • Arabidopsis / cytology
  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Base Sequence
  • Basic Helix-Loop-Helix Transcription Factors
  • Basic-Leucine Zipper Transcription Factors
  • Binding Sites / genetics
  • Binding, Competitive
  • Cells, Cultured
  • Cycloheximide / pharmacology
  • DNA-Binding Proteins / metabolism*
  • Flavonoids / biosynthesis*
  • G-Box Binding Factors
  • Gene Expression Regulation, Enzymologic / drug effects
  • Gene Expression Regulation, Enzymologic / radiation effects
  • Gene Expression Regulation, Plant / drug effects
  • Gene Expression Regulation, Plant / radiation effects
  • Intramolecular Lyases / genetics
  • Intramolecular Lyases / metabolism
  • Leucine Zippers / genetics
  • Light
  • Mixed Function Oxygenases / genetics
  • Mixed Function Oxygenases / metabolism
  • Mutation
  • Oxidoreductases / genetics
  • Oxidoreductases / metabolism
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • Protein Synthesis Inhibitors / pharmacology
  • Proto-Oncogene Proteins c-myb / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Response Elements / genetics*
  • Transcription Factors / metabolism*
  • Transfection
  • Zinc Fingers / genetics

Substances

  • ATR1 protein, Arabidopsis
  • Arabidopsis Proteins
  • Basic Helix-Loop-Helix Transcription Factors
  • Basic-Leucine Zipper Transcription Factors
  • CPC protein, Arabidopsis
  • DNA-Binding Proteins
  • Flavonoids
  • G-Box Binding Factors
  • Plant Proteins
  • Protein Synthesis Inhibitors
  • Proto-Oncogene Proteins c-myb
  • RNA, Messenger
  • Transcription Factors
  • Cycloheximide
  • Mixed Function Oxygenases
  • Oxidoreductases
  • flavanone 3-dioxygenase
  • flavonol synthase
  • Acyltransferases
  • flavanone synthetase
  • Intramolecular Lyases
  • chalcone isomerase