Post Translational Modifications (PTMs)

Protein post-translational modifications play a key role in many cellular processes such as cellular differentiation (Grotenbreg and Ploegh, 2007), protein degradation (Geiss-Friedlander and Melchior, 2007), signaling and regulatory processes (Morrison, et al 2002), regulation of gene expression, and protein-protein interactions. Protein phosphorylation is the most commonly studied area of post-translational modification since it plays a vital role in intracellular signal transduction and is involved in regulating cell cycle progression, differentiation, transformation, development, peptide hormone response, and adaptation (Hubbard and Cohen, 1993; Pawson and Scott, 1997; Hunter, 2000; Cohen, 2002). It has been estimated that one third of mammalian proteins may be phosphorylated and this modification often plays a key role in modulating protein function.

Other modifications under analysis in the MS & Proteomics Resource are palmitoylation, glycosylation, ubiquitination, and SUMOylation, along with other important modifications including methylation, dimethylation, acetylation, decarboxylation, etc. These PTMs are determined using either the digested or purified forms of the proteins by "bottom-up" and/or ”top-down” analyses on the high mass accuracy and high resolution Bruker Apex Qe 9.4 Tesla Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer platform, or the Thermo Scientific LTQ Orbitrap XL.

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