Ultra High-Throughput Drug Screen for Lipid Regulated Ion Channels

A dearth of truly high throughput mechanisms to screen ion channels has hampered the development of pharmacological tools and therapeutics for effectively treating diseases involving ion channels (channelopathies). Ion channels are drug targets for pain, cardiac function, and neurological disorders. We have developed a soluble assay for ion channels using a phosphatidylinositol 4,5-bisphosphate fluorescent probe (FL-PIP2) and detergent purified two pore domain potassium (K2P) and inward rectifying potassium (Kir) channels fused with a nano luciferase luminescent protein (n-Luc). The assay works by bioluminescence energy transfer (BRET). The objective of this grant is to establish a low-cost, soluble approach to screening broad families of ion channels and their many subtypes against libraries of >1 million compounds. We hypothesize that selective allosteric modulators of ion channels can be identified by observing the displacement of the ion channel regulatory lipid PIP2.