The influence of alternative pathways of respiration that utilize branched-chain amino acids following water shortage in Arabidopsis
Journal article, 2016
During dark-induced senescence isovaleryl-CoA dehydrogenase (IVDH) and D-2-hydroxyglutarate dehydrogenase (D-2HGDH) act as alternate electron donors to the ubiquinol pool via the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase (ETF/ETFQO) pathway. However, the role of this pathway in response to other stresses still remains unclear. Here, we demonstrated that this alternative pathway is associated with tolerance to drought in Arabidopsis. In comparison with wild type (WT) and lines overexpressing D-2GHDH, loss-of-function etfqo-1, d2hgdh-2 and ivdh-1 mutants displayed compromised respiration rates and were more sensitive to drought. Our results demonstrated that an operational ETF/ETFQO pathway is associated with plants' ability to withstand drought and to recover growth once water becomes replete. Drought-induced metabolic reprogramming resulted in an increase in tricarboxylic acid (TCA) cycle intermediates and total amino acid levels, as well as decreases in protein, starch and nitrate contents. The enhanced levels of the branched-chain amino acids in loss-of-function mutants appear to be related to their increased utilization as substrates for the TCA cycle under water stress. Our results thus show that mitochondrial metabolism is highly active during drought stress responses and provide support for a role of alternative respiratory pathways within this response.
Respiration
Branched-chain amino acids
Drought
Tricarboxylic acid cycle
Metabolomics
ETF/ETFQO pathway
Author
Marcel V. Pires
Max Planck Institut fur molekulare Physiologie
Universidade Federal de Vicosa
Adilson A. Pereira Júnior
Max Planck Institut fur molekulare Physiologie
David B. Medeiros
Universidade Federal de Vicosa
Danilo M. Daloso
Universidade Federal de Vicosa
Max Planck Institut fur molekulare Physiologie
Phuong Anh Pham
Max Planck Institut fur molekulare Physiologie
Kallyne A. Barros
Universidade Federal de Vicosa
Martin Engqvist
Chalmers, Biology and Biological Engineering, Systems and Synthetic Biology
A. Florian
Max Planck Institut fur molekulare Physiologie
Ina Krahnert
Max Planck Institut fur molekulare Physiologie
V. G. Maurino
Heinrich Heine Universitat
Wagner L. Araújo
Universidade Federal de Vicosa
A. R. Fernie
Max Planck Institut fur molekulare Physiologie
Plant, Cell and Environment
0140-7791 (ISSN) 1365-3040 (eISSN)
Vol. 39 6 1304-1319Subject Categories (SSIF 2011)
Bioinformatics and Systems Biology
DOI
10.1111/pce.12682