My lab integrates mass spectrometry and experimental cell biology using the yeast model system to understand how networks of coordinated PTMs modulate biological function. Now well into the era of genomics and proteomics, it is widely appreciated that understanding individual genes or proteins, although necessary, is often not sufficient to explain the complex behavior observed in living organisms. Indeed, placing context on the dynamic network of relationships that exist between multiple proteins is now one of the greatest challenges in Biology. Post-translational modifications (PTMs, e.g. phosphorylation, ubiquitination and over 200 others), which can be readily quantified by mass spectrometry (MS), often mediate these dynamic relationships through enhancement or disruption of binding and/or catalytic properties that can result in changes in protein specificity, stability, or cellular localization.