Plant Molecular Biology

, Volume 87, Issue 6, pp 615–631

Expression of SOD and APX genes positively regulates secondary cell wall biosynthesis and promotes plant growth and yield in Arabidopsis under salt stress

  • Amrina Shafi
  • Rohit Chauhan
  • Tejpal Gill
  • Mohit K. Swarnkar
  • Yelam Sreenivasulu
  • Sanjay Kumar
  • Neeraj Kumar
  • Ravi Shankar
  • Paramvir Singh Ahuja
  • Anil Kumar Singh
Article

DOI: 10.1007/s11103-015-0301-6

Cite this article as:
Shafi, A., Chauhan, R., Gill, T. et al. Plant Mol Biol (2015) 87: 615. doi:10.1007/s11103-015-0301-6

Abstract

Abiotic stresses cause accumulation of reactive oxygen species (ROS), such as hydrogen peroxide (H2O2) in plants. Sophisticated mechanisms are required to maintain optimum level of H2O2 that acts as signalling molecule regulating adaptive response to salt stress. CuZn-superoxide dismutase (CuZn-SOD) and ascorbate peroxidase (APX) constitute first line of defence against oxidative stress. In the present study, PaSOD and RaAPX genes from Potentilla atrosanguinea and Rheum australe, respectively were overexpressed individually as well as in combination in Arabidopsis thaliana. Interestingly, PaSOD and dual transgenic lines exhibit enhanced lignin deposition in their vascular bundles with altered S:G ratio under salt stress. RNA-seq analysis revealed that expression of PaSOD gene in single and dual transgenics positively regulates expression of lignin biosynthesis genes and transcription factors (NACs, MYBs, C3Hs and WRKY), leading to enhanced and ectopic deposition of lignin in vascular tissues with larger xylem fibres and alters S:G ratio, as well. In addition, transgenic plants exhibit growth promotion, higher biomass production and increased yield under salt stress as compared to wild type plants. Our results suggest that in dual transgenics, ROS generated during salt stress gets converted into H2O2 by SOD and its optimum level was maintained by APX. This basal level of H2O2 acts as messenger for transcriptional activation of lignin biosynthesis in vascular tissue, which provides mechanical strength to plants. These findings reveal an important role of PaSOD and RaAPX in enhancing salt tolerance of transgenic Arabidopsis via increased accumulation of compatible solutes and by regulating lignin biosynthesis.

Keywords

Ascorbate peroxidase Arabidopsis thaliana CuZn-superoxide dismutase Hydrogen peroxide signalling Lignification RNA-seq Secondary cell wall biosynthesis 

Supplementary material

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Supplementary material 1 (PPTX 43794 kb)
11103_2015_301_MOESM2_ESM.pptx (1 mb)
Supplementary material 2 (PPTX 1041 kb)
11103_2015_301_MOESM3_ESM.docx (107 kb)
Supplementary material 3 (DOCX 106 kb)
11103_2015_301_MOESM4_ESM.xlsx (22 kb)
Supplementary material 4 (XLSX 21 kb)

Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Amrina Shafi
    • 1
    • 2
  • Rohit Chauhan
    • 1
  • Tejpal Gill
    • 1
    • 4
  • Mohit K. Swarnkar
    • 1
  • Yelam Sreenivasulu
    • 1
  • Sanjay Kumar
    • 1
  • Neeraj Kumar
    • 3
  • Ravi Shankar
    • 1
  • Paramvir Singh Ahuja
    • 1
    • 2
  • Anil Kumar Singh
    • 1
    • 2
  1. 1.Division of BiotechnologyCSIR-Institute of Himalayan Bioresource TechnologyPalampurIndia
  2. 2.Academy of Scientific and Innovative ResearchNew DelhiIndia
  3. 3.Natural Plant Product DivisionCSIR-Institute of Himalayan Bioresource TechnologyPalampurIndia
  4. 4.National Institute of Arthritis and Musculoskeletal and Skin DiseasesNational Institute of HealthBethesdaUSA

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