In vitro and in cell functional proteomics on natural compounds

Chemical proteomics has acquired a pivotal role in chemical biology because of its peculiar capability to deeply analyze the proteome from many points of view. Proteins identification, characterization and quantification provide a detailed portrait of a biological system. In particular, pharmaceutical research is looking with interest at chemical proteomics because the mechanism of action of bioactive molecules remains one of the main challenge. Particularly, the identification of target proteins and investigation of ligand-receptor interactions are today considered essential steps in the drug discovery and development process. Affinity purification-based mass spectrometry approaches (AP-MS) have emerged as a valuable mean to link bioactive compounds to their cellular targets. In recent years, the application of such techniques led to successful results in determining the macromolecular partners of many interesting bioactive molecules. These techniques require the chemical modifications of the molecule of interest onto a solid matrix, in order to allow the bioactive compound to "fish out" its specific interactors from a cell lysate or a tissue extract. Once eluted, these cellular targets are identified by MS and bioinformatics analysis. Later on, the biological profile of the selected compound toward its cellular interactors is investigated by in vitro and/or in vivo assays.