AgGMP encoding GDP-D-mannose pyrophosphorylase from celery enhanced the accumulation of ascorbic acid and resistance to drought stress in Arabidopsis

PeerJ. 2022 Feb 24:10:e12976. doi: 10.7717/peerj.12976. eCollection 2022.

Abstract

Ascorbic acid (AsA) is an important nutrient in celery, the conversion of D-mannose-1-P to GDP-D-mannose catalyzed by GDP-D-mannose pyrophosphorylase (GMPase) represents the first committed step in the biosynthesis of AsA. To clarify the function of the AgGMP gene of celery, the AgGMP gene was cloned from celery cv. 'Jinnan Shiqin' . It contains an open reading frame (ORF) with the length of 1,086 bp, encoding 361 amino acids. AgGMP protein was highly conserved among different plant species. Phylogenetic analysis demonstrated that the GMP proteins from celery and carrot belonged to the same branch. AgGMP protein was mainly composed of three α-helixes and certain random coils. No signal peptide was found in the AgGMP protein. The subcellular localization indicated that the AgGMP protein was located in the cytoplasm. The relative expression levels of AgGMP in 'Jinnan Shiqin' were significantly up-regulated at 2 h and 4 h under drought stress treatments. AsA contents in transgenic Arabidopsis lines hosting AgGMP gene were higher than that in wild type plants, and the root lengths were also longer in the MS medium containing 300 mM mannitol. The present study provides useful evidence for the functional involvement of AgGMP in regulating AsA accumulation and response to drought stress in celery.

Keywords: Apium graveolens; Arabidopsis thaliana; Ascorbic acid; Drought stress; GDP-D-mannose pyrophosphorylase; Gene expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apium* / genetics
  • Arabidopsis* / genetics
  • Ascorbic Acid
  • Droughts
  • Mannose / metabolism
  • Phylogeny
  • Plant Proteins / chemistry
  • Vegetables / metabolism

Substances

  • Ascorbic Acid
  • Mannose
  • Plant Proteins

Grants and funding

The research was supported by the Key Research and Development Program in Suqian (L202108), the National Natural Science Foundation of China (31272175), and the Priority Academic Program Development of Jiangsu Higher Education Institutions Project (PAPD). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.