Abstract: The invention provides a method of screening a candidate drug, a compound library or a biological extract to identify activators or inhibitors of G-protein-coupled receptors or G-protein-coupled pathways, comprising: (A) using a fluorescent protein fragment complementation assay to construct an assay for one or more steps in a G-protein-coupled pathway; (B) testing the effects of the candidate drugs, compound library, or biological extract on the receptor or pathway of interest; and (C) using the results of the screening to identify specific agents that activate or inhibit the receptor or pathway of interest. The invention also provides a method for identifying a drug lead that modulates the activity of a G-protein-coupled pathway using a fluorescent protein fragment complementation assay. The method of the invention is used to identify agonists, antagonists, activators or inhibitors of G-protein coupled receptors or G-protein-coupled pathways.

Abstract: This invention provides principles, methods and compositions for ascertaining the mechanism of action of pharmacologically important compounds in the context of network biology, across the entire scope of the complex pathways of living cells. Importantly, the principles, methods and compositions provided allow a rapid assessment of the on-pathway and off-pathway effects of lead compounds and drug candidates in living cells, and comparisons of lead compounds with well-characterized drugs and toxicants to identify patterns associated with efficacy and toxicity. The invention will be useful in improving the drug discovery process, in particular by identifying drug leads with desired safety and efficacy and in effecting early attrition of compounds with potential adverse effects in man.

Abstract: This invention provides principles, methods and compositions for ascertaining the mechanism of action of pharmacologically important compounds in the context of network biology, across the entire scope of the complex pathways of living cells. Importantly, the principles, methods and compositions provided allow a rapid assessment of the on-pathway and off-pathway effects of lead compounds and drug candidates in living cells, and comparisons of lead compounds with well-characterized drugs and toxicants to identify patterns associated with efficacy and toxicity. The invention will be useful in improving the drug discovery process, in particular by identifying drug leads with desired safety and efficacy and in effecting early attrition of compounds with potential adverse effects in man.

Abstract: The present invention provides methods for performing pharmacological profiling of a chemical compound, in particular to improve drug safety and efficacy at an early stage in the drug development process. The chemical compound may be a test compound, drug lead, known drug or toxicant. The compound is profiled against a panel of assays. Preferred embodiments of the invention include high-content assays for protein-protein interactions. The compositions and methods of the invention can be used to identify pathways underlying drug efficacy, safety, and toxicity; and to effect attrition of novel compounds with undesirable or toxic properties. The compositions and methods of the invention can also be used to identify new uses of therapeutic agents, to screen libraries of chemical compounds, to perform lead optimization, and to perform studies of structure-activity relationships in the context of intact cells.

Abstract: This invention relates generally to the fields of biology, molecular biology, chemistry and biochemistry. The invention is directed to a large number of novel assays for G-protein-coupled receptors (GPCRs) and their signaling pathways. Methods are described for constructing such assays for one or more steps in a GPCR pathway. The invention can be used for functional characterization of GPCRs, target validation, de-orphanization of receptors, high-throughput screening, high-content screening, pharmacological profiling, and other drug discovery applications. The assays can be used directly to assess whether a compound library or a biological extract contains an agonist or antagonist of a receptor. Assay compositions are also provided. The development of such assays is shown to be straightforward, providing for a broad, flexible and biologically relevant platform for the discovery of novel drugs and natural ligands that act on GPCRs or their cognate pathways.