The Rinehart laboratory is focused on the discovery and characterization of phosphorylation sites in proteins and regulatory networks underlying human disease. We combine quantitative phosphoproteomics with mainstay techniques of molecular biology and physiology to find new roles for kinases, phosphatases, novel substrates, and protein-protein interactions on a system-wide level. Our long term goal is to understand and decode complex signaling networks in physiological systems.
Tens of thousands of phosphorylation sites in diverse eukaryotic proteins have been identified through large scale mass spectrometry studies. For the great majority of these sites, however, the responsible kinase is unknown, and the functional role of phosphorylation is not understood. We have recently made substantial progress towards narrowing this critical gap in knowledge with a new technology that enables site-specific incorporation of phosphoserine into proteins. This technology utilizes an E. coli strain with an expanded genetic code and contains a dedicated sense codon for phosphoserine. We use this breakthrough technology to synthesize human phosphoproteins and accelerate our efforts in “decoding” the human phosphoproteome.