Publication Information
Ito et al., 2009
No external accession available
Abstract
Proteomics. 2009 Sep;9(17):4229-40. doi: 10.1002/pmic.200900064.
A survey of the Arabidopsis thaliana mitochondrial phosphoproteome.
Ito J(1), Taylor NL, Castleden I, Weckwerth W, Millar AH, Heazlewood JL.
Author information:
(1)Australian Research Council Centre of Excellence in Plant Energy Biology, The
University of Western Australia, Crawley, Western Australia, Australia.
Plant mitochondria play central roles in cellular energy production, metabolism
and stress responses. Recent phosphoproteomic studies in mammalian and yeast
mitochondria have presented evidence indicating that protein phosphorylation is
a likely regulatory mechanism across a broad range of important mitochondrial
processes. This study investigated protein phosphorylation in purified
mitochondria from cell suspensions of the model plant Arabidopsis thaliana using
affinity enrichment and proteomic tools. Eighteen putative phosphoproteins
consisting of mitochondrial metabolic enzymes, HSPs, a protease and several
proteins of unknown function were detected on 2-DE separations of Arabidopsis
mitochondrial proteins and affinity-enriched phosphoproteins using the Pro-Q
Diamond phospho-specific in-gel dye. Comparisons with mitochondrial
phosphoproteomes of yeast and mouse indicate that these three species share few
validated phosphoproteins. Phosphorylation sites for seven of the eighteen
mitochondrial proteins were characterized by titanium dioxide enrichment and
MS/MS. In the process, 71 phosphopeptides from Arabidopsis proteins which are
not present in mitochondria but found as contaminants in various types of
mitochondrial preparations were also identified, indicating the low level of
phosphorylation of mitochondrial components compared with other cellular
components in Arabidopsis. Information gained from this study provides a better
understanding of protein phosphorylation at both the subcellular and the
cellular level in Arabidopsis.
DOI: 10.1002/pmic.200900064
PMID: 19688752 [Indexed for MEDLINE]
