Patch-Clamp Proteomics of Single Neurons in Tissue Using Electrophysiology and Subcellular Capillary Electrophoresis Mass Spectrometry

In this project, we enabled mass spectrometry based proteomics characterization of single neurons in sections of the mouse brain. We accessed cells in a whole-cell patch clamp configuration and aspirated a portion of the neuronal soma into the patch clamp probe. The collected aspirate was expelled into a microvial, where proteins were extracted and processed for shot-gun analysis. The resulting trace amounts of protein digests were analyzed on a custom-built microanalytical capillary electrophoresis platform that was connected to an electrospray ionization high-resolution mass spectrometer. This “patch proteomics” technology identified ~150 proteins from triplicate measurement of single dopaminergic neurons in the mouse substantia nigra.