Microsystems for coupled expression and electrophysiology channels

Single-channel electrophysiology is the gold standard for investigating the function of ion channel proteins and their modulation by pharmaceutical drugs, but requires the expression and purification of these channels from cell cultures, which is a notoriously difficult and low-yield process. As an alternative approach, cell-free expression of channel proteins is relatively straightforward, but because of the high cost of the required cell extracts, it is only feasible to obtain very small amounts of expressed protein, insufficient for purification. This proposal aims to develop a new platform for microscale electrophysiology that enables the characterization of ion channels from microliters of a cell-free expression reaction without any purification step.The project will systematically work towards proof of concept, i.e. extensive electrophysiological characterization of a cell-free expressed voltage-gated potassium channel. The main objectives are: 1) the fabrication of elastomeric microwells for the formation of an interdroplet membrane in which ion channels can be incorporated, 2) systematic optimization of the stability of this membrane so that it can be in direct contact with cell-free reaction mixtures, and 3) membrane incorporation of cell-free expressed KvAP for electrophysiological characterization, including drug screening.Ion channels play a central role in many diseases, including seizures, cystic fibrosis, myasthenia gravis, and generalized epilepsy. Many of these channelopathies are chronic conditions which impact heavily on the quality of life. New drugs to treat these diseases or alleviate their symptoms are hence of great value. This project directly addresses a major bottleneck in the drug discovery process by developing a novel method for obtaining pure ion channels that can be directly investigated with microscale electrophysiology.This technology has the clear potential to accelerate ion channel research and drug screening and will benefit biomedical researchers, pharmaceutical companies and the general public. Maximum impact of the research will be realized by professional press releases and by actively approaching the major electrophysiology companies, which have the resources and expertise to commercialize the technology, at specific national and international conferences with an established industry presence.