SP20

Principal Investigator: Florian Meier (Functional Proteomics, Jena University Hospital) & Daria Zibrova (Institute of Molecular Cell Biology, Jena University Hospital)

Felix Schneidmadel (PhD): Survey of the Post-Translational Modification Landscape in Ageing via
Trapped Ion Mobility Mass Spectrometry

Our current knowledge about biological processes involving protein post-translational modifications (PTMs) has been fueled by the widespread use of mass spectrometry-based proteomics. However, interactions between different PTMs remain largely elusive because state-of-the-art strategies typically analyze only one PTM at a time and involve tailored workflows to enrich a specific PTM of interest based on chemical or biochemical affinity. Conversely, all other peptides are discarded and, more critically, efficient enrichment strategies are lacking for most of the several hundreds of known in vivo modifications. Here, we propose to use an ‘open search’ bioinformatics approach combined with deep peptide fractionation to survey the PTM landscape of model systems in aging. We build on the recent development of rapid and sensitive trapped ion mobility mass spectrometry (TIMS-MS), which adds an additional dimension of separation as compared to conventional liquid chromatography – mass spectrometry.

Andreas Will (PhD): Identificatio of novel O-GlNAcylated substrates in endothelial cells and investigation of their role in senescence and ageing

The modification of proteins with O-linked N-acetylglucosamine (O-GlcNAc) is an essential posttranslational modification that regulates protein function. Increased O-GlcNAcylation underlies the aetiology of age-related vascular pathologies via unknown mechanisms. So far, O-GlcNAcylated substrates in vascular endothelium are barely studied and the identification of O-GlcNAc modification sites remains a technical challenge. We aim to establish a novel mass spectrometry-based approach for the identification of O-GlcNAcylated proteins in vascular endothelial cells using ion mobility spectrometry. With this workflow, we will study the role of O-GlcNAcylation in endothelial cell function and senescence.