The role of tonoplast protein phosphorylation in activity regulation and protein targeting
Final Report Abstract
In conclusion, the QconCAT standard peptides are very useful in experiments where a defined set of target proteins is to be analyzed, as for example in this study the focus was specifically on vacuolar (sugar) transporters. The use of these spiked-in standards clearly does exceed the range of quantitation to include more low-abundant proteins compared to a simple label-free experiment. We showed that salinity stress results in large changes in vacuolar transporter abundances, particularly for vacuolar ATPases AVP1, members of the ERDL-transporter family as well as TMT2. Since salinity is known to increase the sugar content in vacuoles, we suggest that this increase in vacuolar sugar content is achieved by an increase in transporter presence in the tonoplast. For mutants in AP-3, particularly proteins with transport functions, such as aquaporins and plasma membrane ATPase showed differential protein distribution profiles across the density gradient. For mutants in AP-4 also plasma membrane ATPases and proteins from lipid metabolism were differentially distributed. Other proteins, such as particularly receptor kinases were depleted from the AP-3 mutant membrane system, possibly due to degradation after mis-targeting. In AP-4 mutants, membrane preparations were depleted for cytochrome P450 proteins, cell wall proteins and receptor kinases.
Publications
- (2012) Cold acclimation induces changes in Arabidopsis tonoplast protein abundance and activity and alters phosphorylation of tonoplast monosaccharide transporters. Plant J. 69: 529-541
Schulze W.X., Schneider T., Starck S., Martinoia E. and Trentmann O.
(See online at https://doi.org/10.1111/j.1365-313X.2011.04812.x) - (2014) In vivo cross-linking combined with mass spectrometry analysis reveals receptor-like kinases and Ca2+ signaling proteins as putative interaction partners of pollen plasma membrane H+ ATPases. J. Proteom. 108C: 17-29
Pertl-Obermeyer, H., Schulze, W.X. and Obermeyer, G.
(See online at https://doi.org/10.1016/j.jprot.2014.05.001) - (2015) Databases for plant phosphoproteomics. Meth. Mol. Biol. 1306: 207-216
Schulze, W.X., Yao, Q. and Xu, D.
(See online at https://doi.org/10.1007/978-1-4939-2648-0_16) - (2015) Kinase activity and specificity assay using synthetic peptides. Methods in Molecular Biology, 1306: 97-104
Wu, X.N. and Schulze, W.X.
(See online at https://doi.org/10.1007/978-1-4939-2648-0_7) - (2015) Phosphopeptide profiling of receptor kinase mutants. Methods in Molecular Biology, 1306: 71-79
Wu, X.N. and Schulze, W.X.
(See online at https://doi.org/10.1007/978-1-4939-2648-0_5) - (2016) From Phosphoproteome to Modeling of Plant Signaling Pathways. Meth. Mol. Biol. 1394: 245-259
Zakhartsev M, Pertl-Obermeyer H, Schulze WX
(See online at https://doi.org/10.1007/978-1-4939-3341-9_18)
