Chemical proteomics: terra incognita for novel drug target profiling

The growing demand for new therapeutic strategies in the medical and pharmaceutic fields has resulted in a pressing need for novel druggable targets.Paradoxically,however,the targets of certain drugs that are already widely used in clinical practice have largely not been annotated.Because the pharmacologic effects of a drug can only be appreciated when its interactions with cellular components are clearly delineated,an integrated deconvolution of drug-target interactions for each drug is necessary.The emerging field of chemical proteomics represents a powerful mass spectrometry (MS)-based affinity chromatography approach for identifying proteome-wide small molecule-protein interactions and mapping these interactions to signaling and metabolic pathways.This technique could comprehensively characterize drug targets,profile the toxicity of known drugs,and identify possible off-target activities.With the use of this technique,candidate drug molecules could be optimized,and predictable side effects might consequently be avoided.Herein,we provide a holistic overview of the major chemical proteomic approaches and highlight recent advances in this area as well as its potential applications in drug discovery.