These authors contributed equally to this work.
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Research Article
Proteomic analysis of salt-responsive ubiquitin-related proteins in rice roots
Article first published online: 22 JUN 2012
DOI: 10.1002/rcm.6271
Copyright © 2012 John Wiley & Sons, Ltd.
Additional Information
How to Cite
Liu, C.-W., Hsu, Y.-K., Cheng, Y.-H., Yen, H.-C., Wu, Y.-P., Wang, C.-S. and Lai, C.-C. (2012), Proteomic analysis of salt-responsive ubiquitin-related proteins in rice roots. Rapid Commun. Mass Spectrom., 26: 1649–1660. doi: 10.1002/rcm.6271
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These authors contributed equally to this work.
Publication History
- Issue published online: 22 JUN 2012
- Article first published online: 22 JUN 2012
- Manuscript Accepted: 9 MAY 2012
- Manuscript Revised: 4 MAY 2012
- Manuscript Received: 14 FEB 2012
RATIONALE
Ubiquitination of proteins plays an important role in regulating a myriad of physiological functions in plants such as xylogenesis, senescence, cell cycle control, and stress response. However, only a limited number of proteins in plants have been identified as being ubiquitinated in response to salt stress. The relationships between ubiquitination and salt-stress responses in plants are not clear.
METHODS
Rice (Oryza sativa) seedlings from the same genetic background with various salt tolerances exposed to salt stress were studied. The proteins of roots were extracted then analyzed using western blotting against ubiquitin. Differentially expressed ubiquitinated proteins were identified by nanospray liquid chromatography/tandem mass spectrometry (nano-LC/MS/MS) and quantified by label-free methods based on the Exponentially Modified Protein Abundance Index (emPAI) and on the peak areas of XIC spectra derived from ubiquitinated peptides. In addition, we performed a gel-based shotgun proteomic analysis to detect the ubiquitinated proteome that may be involved in response to salt stress.
RESULTS
The expressions of ubiquitination on pyruvate phosphate dikinase 1, heat shock protein 81–1, probable aldehyde oxidase 3, plasma membrane ATPase, cellulose synthase A catalytic subunit 4 [UDP-forming] and cyclin-C1-1 were identified and compared before and after salt treatment. The functions of those ubiquitinated proteins were further discussed for defence against salt stress. In addition, a large number of ubiquitinated proteins were successfully identified as well in this study.
CONCLUSIONS
The ubiquitination of proteins affected the protective mechanisms in rice seedlings to resist the salt stress during the initial phase. The findings in the present study also demonstrate that the regulated mechanisms through protein ubiquitination are important for rice seedlings against salt stress. Copyright © 2012 John Wiley & Sons, Ltd.