Biosynthesis of catechin components is differentially regulated in dark-treated tea (Camellia sinensis L.)

Plant Physiol Biochem. 2014 May;78:49-52. doi: 10.1016/j.plaphy.2014.02.017. Epub 2014 Mar 3.

Abstract

Tea (Camellia sinensis L.) is a crop with both commercial and medicinal value with remarkably high polyphenol content in the form of catechins. To understand the molecular regulation of catechin biosynthesis in tea, we treated the tea plants with darkness. We used qRT-PCR to validate the expression of genes involved in catechin biosynthesis. It indicated that dark treatment displayed different effects on the genes participating in tea flavonoid (FL) pathway. The early genes of FL biosynthesis pathway, CHSI, F3H and DFR, remained at steady expression levels when treated by darkness. It is noteworthy that the expression level of LAR increased and the level of ANS decreased under dark conditions. The vanillin assay showed that the dark-treated plants contained lower levels of total catechins than those grown under normal conditions. The HPLC analysis further demonstrated the changes in biosynthesis of catechins under these conditions. In accordance with the gene expression pattern, the content of epicatechins (ECs) declined and that of catechins (Cs) was elevated in response to the darkness. Our study uncovered the molecular mechanisms and biochemical changes of shading in tea cultivation.

Keywords: Catechins; Darkness; Flavonoid pathway; Tea; Transcriptional regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyltransferases / genetics
  • Acyltransferases / metabolism
  • Alcohol Oxidoreductases / genetics
  • Alcohol Oxidoreductases / metabolism
  • Anthocyanins / biosynthesis
  • Biosynthetic Pathways / genetics*
  • Biosynthetic Pathways / radiation effects
  • Camellia sinensis / genetics*
  • Camellia sinensis / metabolism*
  • Catechin / biosynthesis*
  • Chromatography, High Pressure Liquid
  • Darkness
  • Gene Expression Regulation, Enzymologic / radiation effects
  • Gene Expression Regulation, Plant / radiation effects
  • Light
  • Mixed Function Oxygenases / genetics
  • Mixed Function Oxygenases / metabolism
  • NADH, NADPH Oxidoreductases / genetics
  • NADH, NADPH Oxidoreductases / metabolism
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tea / chemistry

Substances

  • Anthocyanins
  • Plant Proteins
  • Tea
  • Catechin
  • Mixed Function Oxygenases
  • Alcohol Oxidoreductases
  • dihydroflavanol 4-reductase
  • flavanone 3-dioxygenase
  • NADH, NADPH Oxidoreductases
  • Acyltransferases
  • flavanone synthetase