Every cell in the human body contains proteins, and these proteins are essential to the proper functioning of every part of our body. Proteins are not soloists, though – like an ensemble, they interact with other proteins, in a process called protein-protein interactions, or PPIs. When these interactions go awry, disease results. Because of their involvement in causing diseases, understanding how these interactions work is essential to finding targets for intervention and developing drugs that will do so. In phase 1 of this competition, Dr. Igor Stagljar of the University of Toronto and his team developed a new method for studying PPI interactions, called Split Intein-Mediated Protein Ligation (SIMPL), which outperforms current methods for studying PPIs. They now propose to further develop SIMPL as a groundbreaking assay for biomedical research by combining it with mass spectrometry to extend its capabilities and facilitate a more powerful and convenient platform. The team will also use SIMPL to globally map PPIs involved in disease, particularly cancer development. Finally, they will use SIMPL as a drug-screening platform to identify chemicals that can interfere in PPIs implicated in cancer development. SIMPL will be a transformative technology for studying functional genomics. It will displace current methods of studying PPIs, accelerate our understanding of cell physiology and disease development and identify new therapies for some diseases. SIMPL will be commercialized through a newly founded Canadian company, ProteinNetwork Tx, ensuring both economic and health benefits for Canada.