Differential Expression of Two Flavonoid 3'-hydroxylase cDNAs Involved in Biosynthesis of Anthocyanin Pigments and 3-deoxyanthocyanidin Phytoalexins in Sorghum

Plant Cell Physiol. 2006 Oct;47(10):1412-9. doi: 10.1093/pcp/pcl003. Epub 2006 Aug 30.

Abstract

Three unique sorghum flavonoid 3'-hydroxylase (F3'H) cDNAs (SbF3'H1, SbF3'H2 and SbF3'H3) were discovered through bioinformatics analysis. Their encoded proteins showed >60% identity to the Arabidopsis TT7 (F3'H) protein. Overexpression of SbF3'H1 or SbF3'H2 restored the ability of tt7 mutants to produce 3'-hydroxylated flavonoids, establishing their roles as functional F3'H enzymes. In sorghum mesocotyls, SbF3'H1 expression was involved in light-specific anthocyanin accumulation while SbF3'H2 expression was involved in pathogen-specific 3-deoxyanthocyanidin synthesis. No SbF3'H3 expression was detected in all tissues examined. The sorghum mesocotyls represent a good system for investigation of differential regulation of F3'H genes/alleles responding to different external stimuli.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Anthocyanins / biosynthesis
  • Anthocyanins / chemistry
  • Cytochrome P-450 Enzyme System / biosynthesis
  • Cytochrome P-450 Enzyme System / genetics*
  • DNA, Complementary / analysis
  • Gene Expression Regulation, Enzymologic*
  • Gene Expression Regulation, Plant*
  • Genes, Plant
  • Mixed Function Oxygenases / biosynthesis
  • Mixed Function Oxygenases / genetics*
  • Molecular Sequence Data
  • Molecular Structure
  • Sesquiterpenes
  • Sorghum / genetics*
  • Terpenes / chemistry
  • Terpenes / metabolism

Substances

  • Anthocyanins
  • DNA, Complementary
  • Sesquiterpenes
  • Terpenes
  • phytoalexins
  • Cytochrome P-450 Enzyme System
  • Mixed Function Oxygenases
  • flavonoid 3'-hydroxylase

Associated data

  • GENBANK/DQ787855
  • GENBANK/DQ787856
  • GENBANK/DQ787857