Wheat mitochondrial proteomes provide new links between antioxidant defense and plant salinity tolerance.
The mitochondrial proteome and differences associated with salt tolerance have been investigated in Australian commercial varieties of wheat. Mitochondria isolated from shoots were used to generate a wheat mitochondrial reference map; 68 unique wheat mitochondrial proteins were identified from 192 gel spots using 2D PAGE and LC-MS/MS. This analysis also provided MS/MS spectra for 199 proteotypic peptides as a foundation for the development of targeted proteomics to study the respiratory apparatus in wheat. Using this reference map and 2D DIGE, we have found quantitative differences in the shoot mitochondrial proteomes of v. Wyalkatchem and v. Janz, two commercially important wheat varieties that are known from a range of experiments to differ in salinity tolerance. These proteins included Mn-superoxide dismutase (Mn-SOD), cysteine synthase, nucleotide diphosphate kinase, and the voltage dependent anion channel (VDAC). Antibodies to the mitochondrial alternative oxidase (AOX), previously linked to reduced ROS formation from the electron transport chain and salt tolerance in Arabidopsis, also showed a commensurate higher abundance in v. Wyakatchem in both control and salt-treated conditions. Together, the data presented here suggest that differences in mitochondrial ROS defense pathways in the mitochondrial proteomes of key Australian wheat varieties correlate with whole-plant salinity tolerance.
ARC Centre of Excellence in Plant Energy Biology & Centre for Comparative Analysis of Biomolecular Networks, M316, The University of Western Australia, 35 Stirling Highway, Crawley,WA 6009, Australia.
Richard P
RP
Jacoby
A Harvey
AH
Millar
Nicolas L
NL
Taylor
D000595:Amino Acid Sequence; D000975:Antioxidants / Q000378:metabolism; D003547:Cysteine Synthase / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D013058:Mass Spectrometry; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000032:analysis* / Q000378:metabolism; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000378:metabolism; D010940:Plant Proteins / Q000032:analysis* / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D055049:Salt Tolerance; D055051:Salt-Tolerant Plants / Q000378:metabolism; D013045:Species Specificity; D013482:Superoxide Dismutase / Q000378:metabolism; D014908:Triticum / Q000378:metabolism*; D000099188:Alternative Oxidase
D000975:Antioxidants; D003547:Cysteine Synthase; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D013482:Superoxide Dismutase; D000099188:Alternative Oxidase