High Throughput Methods for Single Cell Proteomics

点击翻译按钮获取中文摘要

PROJECT SUMMARY/ ABSTRACT To understand deviations in normal function of neurons and neuronal circuits brought on by disease, we will develop methods using patch clamping to measure the electrophysiology of individual neurons and then use mass spectrometry-based proteomics to measure the proteome. Now that neurons can be created from the skin cells of patients harboring disease genes to determine genotype to phenotype relationships between the genetic defects and electrophysiology, the methods we develop have great potential to significantly improve our ability to study human diseases of the brain. “Brain” organoids are also being created from skin cells to recapitulate a 3-dimensional environment for neurons and to include excitatory and inhibitory neurons. The ability to concurrently measure electrophysiology and protein expression will allow a determination of how disease related perturbations to neurons and other cells are related to molecular phenotypes. Single cell RNA-SEQ is used to measure gene expression in neurons, but gene expression profiles fail to account for rates of protein synthesis, degradation, proteostasis, post translational modification and enzymatic activity, all of which are critical cellular functions accomplished by proteins. Single cell mass spectrometry has been applied to neurons to measure metabolites and neuropeptides, but efforts to measure the proteome have lagged. We have established that proteins can be measured in neurons after electrophysiology, but here we propose to greatly increase the scale of measurements as well as the throughput. These methods will be broadly applicable as patch clamping techniques is a widely used technique to measure ionic currents in a variety of cell types including neurons, cardiomyocytes, muscle fibers and pancreatic beta cells. Furthermore, these methods will enable experiments to determine the mechanism of action of drugs that restore normal electrophysiology to neurons