Proteomic analysis of tea plants (Camellia sinensis) with purple young shoots during leaf development

PLoS One. 2017 May 16;12(5):e0177816. doi: 10.1371/journal.pone.0177816. eCollection 2017.

Abstract

Tea products made from purple leaves are highly preferred by consumers due to the health benefits. This study developed a proteome reference map related to color changes during leaf growth in tea (Camellia sinensis) plant with purple young shoots using two-dimensional electrophoresis (2-DE). Forty-six differentially expressed proteins were detected in the gel and successfully identified by using MALDI-TOF/TOF-MS. The pronounced changes in the proteomic profile between tender purple leaves (TPL) and mature green leaves (MGL) included: 1) the lower activity of proteins associated with CO2 assimilation, energy metabolism and photo flux efficiency and higher content of anthocyanins in TPL than those in MGL may protect tender leaves against photo-damage; 2) the higher abundance of chalcone synthase (CHS), chalcone isomerase (CHI) and flavonol synthase (FLS) likely contributes to the synthesis of anthocyanins, catechins and flavonols in TPL tissues; 3) higher abundance of stress response proteins, such as glutathione S-transferases (GST) and phospholipid hydroperoxide glutathione peroxidase (PHGPx), could enhance the tolerance of TPL tissues to adverse condition in; and 4) the increased abundance of proteins related to protein synthesis, nucleic acids and cell wall proteins should be beneficial for the proliferation and expansion of leaf cell in TPL tissues. qPCR analysis showed that the expression of differentially abundant proteins was regulated at the transcriptional level. Therefore, the results indicated that higher abundance of CHI and CHS may account for the production of the purple-shoot phenotype in Wuyiqizhong 18 and thereby, enhancing the anthocyanin biosynthesis. The higher abundance of glutamine synthetase (GS) proteins related to the theanine biosynthesis may improve the flavor of tea products from TPL materials. Thus, this work should help to understand the molecular mechanisms underlying the changes in leaf color alteration.

MeSH terms

  • Camellia sinensis / growth & development
  • Camellia sinensis / metabolism*
  • Carbon Dioxide / metabolism
  • Energy Metabolism
  • Glutamate-Ammonia Ligase / genetics
  • Glutamate-Ammonia Ligase / metabolism
  • Oxidative Stress
  • Plant Leaves / growth & development*
  • Plant Leaves / metabolism
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plant Shoots / growth & development
  • Plant Shoots / metabolism
  • Proteome / genetics
  • Proteome / metabolism*

Substances

  • Plant Proteins
  • Proteome
  • Carbon Dioxide
  • Glutamate-Ammonia Ligase

Grants and funding

This work was supported by funding from the National 863 Program (2013AA10260605), Science and Technology Major Project of Fujian province (2015NZ0002-1) and the earmarked fund for Modern Agro-industry Technology Research System (CARS-23). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.