African Journal of Plant Science
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Article Number - FE7DD4164287


Vol.11(6), pp. 252-263 , June 2017
DOI: 10.5897/AJPS2017.1551
ISSN: 1996-0824



Full Length Research Paper

Oversensitivity of Arabidopsis gad1/2 mutant to NaCl treatment reveals the importance of GABA in salt stress responses



Dereje Worku Mekonnen
  • Dereje Worku Mekonnen
  • Botanical Institute II, Cologne Biocenter, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany
  • Google Scholar







 Received: 29 March 2017  Accepted: 28 April 2017  Published: 30 June 2017

Copyright © 2017 Author(s) retain the copyright of this article.
This article is published under the terms of the Creative Commons Attribution License 4.0


Salt stress is one of the major problems in agricultural fields. Currently, more than 20% of irrigated agricultural lands are affected by salinity. High concentrations of sodium affects plant growth by competing with the uptake of important ions like potassium (K+), and posing osmotic stress. Some plant species developed mechanisms such as modifying cellular metabolism to minimize effects of high salt concentrations. Gamma-aminobutyric acid (GABA) accumulation during salt stress is one of the results of modifications in cellular metabolism. However, whether this response is specific or not has not been shown before. Here, it was hypothesized that GABA accumulation is needed to counter the effects of salt stress. For that, GABA-depleted Arabidopsis gad1/2 mutant was investigated for altered response under salt stress. Indeed, the double mutant was oversensitive to 150 mM NaCl treatment. Furthermore, the mutant was oversensitive to osmotic stress; since the double mutant showed reduced shoot water content after 300 mM mannitol treatment. Comparison of metabolites between salt-treated wild type and gad1/2 mutant showed that GABA shunt plays a central role in modulating the carbon and nitrogen metabolism. Taken together, the findings show that GABA accumulation under salt stress conditions plays an important role to overcome the high salt concentration damage.

 

Key words: Salt stress, osmotic stress, GABA-shunt, tricarboxylic acid (TCA) cycle intermediates, potassium, transporters.

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APA Mekonnen, D. W. (2017). Oversensitivity of Arabidopsis gad1/2 mutant to NaCl treatment reveals the importance of GABA in salt stress responses. African Journal of Plant Science, 11(6), 252-263.
Chicago Dereje Worku Mekonnen,. "Oversensitivity of Arabidopsis gad1/2 mutant to NaCl treatment reveals the importance of GABA in salt stress responses." African Journal of Plant Science 11, no. 6 (2017): 252-263.
MLA Dereje Worku Mekonnen,. "Oversensitivity of Arabidopsis gad1/2 mutant to NaCl treatment reveals the importance of GABA in salt stress responses." African Journal of Plant Science 11.6 (2017): 252-263.
   
DOI 10.5897/AJPS2017.1551
URL http://academicjournals.org/journal/AJPS/article-abstract/FE7DD4164287

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