Location: Plant, Soil and Nutrition ResearchTitle: Quantitative iTRAQ proteomics revealed possible roles for antioxidant proteins in sorghum aluminum tolerance
|ZHOU, DANGWEI - Cornell University - New York|
|ZHANG, JINBIAO - Cornell University - New York|
|JIANG, FEI - Boyce Thompson Institute|
|JIA, XIAOMIN - Cornell University - New York|
|Thannhauser, Theodore - Ted|
Submitted to: Journal of Proteome Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2016
Publication Date: 1/9/2017
Citation: Zhou, D., Yang, Y., Zhang, J., Jiang, F., Jia, X., Craft, E.J., Thannhauser, T.W., Kochian, L.V., Liu, J. 2017. Quantitative iTRAQ proteomics revealed possible roles for antioxidant proteins in sorghum aluminum tolerance. Journal of Proteome Research. 7:2043.
Interpretive Summary: The sorghum root tip is a major target of Al toxicity. However, the responses of the sorghum root tip to Al stress have not been investigated at protein expression levels. This study shows that antioxidant system and the phenyhlpropanoid pathway are involved in plants’ responses to Al toxicity.
Technical Abstract: Aluminum (Al) toxicity inhibits root growth and nutrient uptake and limits crop yields on acid soils worldwide. However, little quantitative information is available on protein expression profiles under Al stress in crops. In this study, we report on the identification of potential Al responsive proteins from root tips of Al sensitive BR007 and Al tolerant SC566 sorghum lines using a strategy employing Isobaric Tags for Relative and Absolutely Quantification (iTRAQ) and 2-dimensional liquid chromatography coupled to tandem mass spectrometry (2D-LC-MS/MS). A total of 771 and 329 unique proteins with abundance changes of > 1.5 fold or < 0.67 fold were identified in BR007 and SC566, respectively. The corresponding proteins include antioxidant/detoxifying enzymes, carbohydrate metabolism-related, translation-related and phenylpropanoid-biosynthesis-related proteins. Protein interaction and pathway analyses indicated that proteins involved in the antioxidant system were more abundant in the tolerant line than in the sensitive one after Al treatment, while opposite trends were observed for proteins involved in the phenylpropanoid pathway required for lignin biosynthesis. Further characterization of enzyme activities showed that peroxidases and the fine-tuning of balance between production and consumption of reactive oxygen species (ROS) could play an important role in sorghum Al tolerance and in the regulation of lignin biosynthesis. In the Al sensitive sorghum line, higher levels of ROS accumulation in root tips under Al stress due to decreased activity of antioxidant enzymes (peroxidase) could also lead to higher lignin production and hyper-accumulation of toxic Al in cell walls.