Simultaneous expression of abiotic stress responsive transcription factors, AtDREB2A, AtHB7 and AtABF3 improves salinity and drought tolerance in peanut (Arachis hypogaea L.)

PLoS One. 2014 Dec 4;9(12):e111152. doi: 10.1371/journal.pone.0111152. eCollection 2014.

Abstract

Drought, salinity and extreme temperatures are the most common abiotic stresses, adversely affecting plant growth and productivity. Exposure of plants to stress activates stress signalling pathways that induce biochemical and physiological changes essential for stress acclimation. Stress tolerance is governed by multiple traits, and importance of a few traits in imparting tolerance has been demonstrated. Under drought, traits linked to water mining and water conservation, water use efficiency and cellular tolerance (CT) to desiccation are considered to be relevant. In this study, an attempt has been made to improve CT in drought hardy crop, peanut (Arachis hypogaea L., cv. TMV2) by co-expressing stress-responsive transcription factors (TFs), AtDREB2A, AtHB7 and AtABF3, associated with downstream gene expression. Transgenic plants simultaneously expressing these TFs showed increased tolerance to drought, salinity and oxidative stresses compared to wild type, with an increase in total plant biomass. The transgenic plants exhibited improved membrane and chlorophyll stability due to enhanced reactive oxygen species scavenging and osmotic adjustment by proline synthesis under stress. The improvement in stress tolerance in transgenic lines were associated with induced expression of various CT related genes like AhGlutaredoxin, AhAldehyde reductase, AhSerine threonine kinase like protein, AhRbx1, AhProline amino peptidase, AhHSP70, AhDIP and AhLea4. Taken together the results indicate that co-expression of stress responsive TFs can activate multiple CT pathways, and this strategy can be employed to improve abiotic stress tolerance in crop plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acclimatization / genetics
  • Arabidopsis / genetics
  • Arabidopsis Proteins / biosynthesis
  • Arabidopsis Proteins / genetics*
  • Arachis / genetics*
  • Arachis / physiology
  • Basic-Leucine Zipper Transcription Factors / biosynthesis
  • Basic-Leucine Zipper Transcription Factors / genetics*
  • Chlorophyll / genetics
  • Droughts*
  • Gene Expression Regulation, Plant
  • Oxidative Stress / genetics
  • Plant Leaves / genetics
  • Plant Leaves / growth & development
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / growth & development
  • Reactive Oxygen Species / metabolism
  • Salinity
  • Seedlings / genetics
  • Seedlings / growth & development
  • Stress, Physiological / genetics*
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics*

Substances

  • ABF3 protein, Arabidopsis
  • Arabidopsis Proteins
  • Basic-Leucine Zipper Transcription Factors
  • DREB2A protein, Arabidopsis
  • Reactive Oxygen Species
  • Transcription Factors
  • Chlorophyll

Grant support

This work was supported by grants from Department of Biotechnology (DBT), Ministry of Science and technology, Government of India. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.