Phosphoprotein Analysis

Clustering of time-resolved phosphorylation changes upon nutrient resupply after starvation.

(Click on the graphic to see all clusters 1 - 16)

Clustering of time-resolved phosphorylation changes upon nutrient resupply after starvation.

(Click on the graphic to see all clusters 1 - 16)

Protein phosphorylation is the most common posttranslational modification with regulatory function. Phosphorylation can induce changes in protein activity and provide docking sites for interaction of other signalling proteins or the formation of protein complexes. Thus, specific protein modification and subsequent modification-dependent protein-protein interactions are important features of signalling networks, which often function as 'molecular switches'.

Phosphorylation of membrane proteins will be analyzed in response to nutrient stress in form of starvation-resupply experiments. Affinity purification methods will used to enrich phosphoproteins and phosphopeptides before identification by mass spectrometry.

In order to efficiently analyse phopshorylation sites, we have set up PhosPhAt, a public database of plant protein phosphorylation sites. This growing public resource hosts mass spectra and phosphorylation site indentifications based on mass spectrometric evidence from large scale experiments. Based on these experimental information we have developed a plant specific predictor for protein phosphorylation sites, that is also integrated in the PhosPhAt resource.

Recommended Reading

Schulze WX (2010) Proteomic approaches to understand protein phosphorylation in pathway modulation. Current Opinion in Plant Biology 13: 1-8

Schulze WX, Usadel B (2010) Quantitation in Mass-Spectrometry-Based Proteomics. Annual Review of Plant Biology 61: 491-516

Durek P, Schmidt R, Heazlewood JL, Jones A, MacLean D, Nagel A, Kersten B, Schulze WX (2010) PhosPhAt: The Arabidopsis thaliana phosphorylation site database. An update. Nucleic Acids Research 38: D828-834

Riano-Pachon DM, Kleesen S, Neigenfind J, Durek P, Weber E, Engelsberger WR, Walther D, Selbig J, Schulze WX, Kersten B (2010) Proteome-wide survey of phosphorylation patterns affected by nuclear DNA polymorphisms in Arabidopsis thaliana. BMC Genomics 11: 411

Kersten, B, Agrawal, GK, Durek P, Neigenfind J, Schulze WX, Walther D, Rakwal R (2009) Plant phosphoproteomics: An update. Proteomics 9: 964-988

Heazlewood JL, Durek P, Hummel J, Selbig J, Weckwerth W, Walther D, Schulze WX (2008) PhosPhAt: A Database of phosphorylation sites in Arabidopsis thaliana and a plant specific phosphorylation site predictor. Nucleic Acids Research36: D1015-D1021

Niittylä T, Fuglsang AT, Palmgren MG, Frommer WB, Schulze WX (2007) Temporal analysis of sucrose-induced phosphorylation changes in plasma membrane proteins of Arabidopsis. Molecular and Cellular Proteomics6 (10): 1711-1726