The phosphoproteome of Arabidopsis plants lacking the oxidative signal-inducible1 (OXI1) protein kinase
Article first published online: 22 DEC 2010
© 2010 The Authors. New Phytologist © 2010 New Phytologist Trust
Volume 190, Issue 1, pages 49–56, April 2011
How to Cite
Howden, A. J.M., Salek, M., Miguet, L., Pullen, M., Thomas, B., Knight, M. R. and Sweetlove, L. J. (2011), The phosphoproteome of Arabidopsis plants lacking the oxidative signal-inducible1 (OXI1) protein kinase. New Phytologist, 190: 49–56. doi: 10.1111/j.1469-8137.2010.03582.x
- Issue published online: 25 FEB 2011
- Article first published online: 22 DEC 2010
- Received: 17 September 2010, Accepted: 4 November 2010
- Arabidopsis thaliana;
- OXI1 kinase;
- protein turnover;
- ROS signalling
- •The AGC protein kinase OXI1 is a key protein in plant responses to oxidative signals, and is important for two oxidative burst-mediated processes: basal resistance to microbial pathogens and root hair growth. To identify possible components of the OXI1 signalling pathway, phosphoproteomic techniques were used to detect alterations in the abundance of phosphorylated proteins and peptides in an oxi1 null mutant of Arabidopsis thaliana.
- •The relative abundance of phosphorylated proteins was assessed either using two-dimensional gel electrophoresis and staining with the phosphoprotein stain Pro-Q Diamond or by the identification and quantification, by mass spectrometry, of stable-isotope labelled phosphopeptides.
- •A number of proteins show altered phosphorylation in the oxi1 mutant. Five proteins, including a putative F-box and 3-phosphoinositide-dependent kinase 1, show reduced phosphorylation in the oxi1 mutant, and may be direct or indirect targets of OXI1. Four proteins, including ethylene insensitive 2 and phospholipase d-gamma, show increased phosphorylation in the oxi1 mutant.
- •This study has identified a range of candidate proteins from the OXI1 signalling pathway. The diverse activities of these proteins, including protein degradation and hormone signalling, may suggest crosstalk between OXI1 and other signal transduction cascades.