Odyssey Thera Inc.

Jane Lamerdin

Stephen William Watson Michnick

Marnie L MacDonald

Ingrid Remy

Helen Yu

John K Westwick

Marnie Macdonald

The present invention is directed to Protein-fragment Complementation Assays (PCAs) and assay compositions based on fluorescent proteins. The invention provides methods for fragmenting fluorescent proteins and generating mutant fragments with desired spectral characteristics for PCA. The invention encompasses assays and compositions based on fluorescent proteins from the speciesand. In particular, the invention is directed to fragments of mutant fluorescent proteins having improved spectral properties over the wild-type proteins. The invention encompasses fragments of mutant versions ofgreen fluorescent protein (GFP), in particular yellow fluorescent proteins (EYFP and super-EYFP), 'Venus', cyan, 'citrine', blue, cyan-green, and photoactivatable variants of GFP The invention also encompasses red fluorescent PCAs based on Discosoma red fluorescent protein (RFP PCA) and a kindling fluorescent protein PCA (KFP1 PCA) derived from. Any useful mutation of a fluorescent protein can be engineered into a fragment, generating a wide range of assays useful for drug discovery, target validation, high-throughput screening, high-content screening, pathway mapping, drug mechanism-of-action studies, biosensors, and diagnostics.

Fragments of fluorescent proteins for protein fragment complementation assays

The present invention provides protein fragment complementation assays for drug discovery, in particular to identify compounds that activate or inhibit cellular pathways. Based on the selection of an interacting protein pair combined with an appropriate PCA reporter, the assays may be run in high-throughput or high-content mode and may be used in automated screening of libraries of compounds. The interacting pair may be selected by cDNA library screening; by gene-by-gene interaction mapping; or by prior knowledge of a pathway. Fluorescent and luminescent assays can be constructed using the methods provided herein. The selection of suitable PCA reporters for high-throughput or high-content (high-context) assay formats is described for a diversity of reporters, with particular detail provided for examples of monomeric enzymes and fluorescent proteins. Methods are described for constructing such assays for one or more steps in a biochemical pathway; testing the effects of compounds from combinatorial, natural product, peptide, antibody, nucleic acid or other diverse libraries on the protein or pathway(s) of interest; and using the results of the screening to identify specific compounds that activate or inhibit the protein or pathway(s) of interest. Single-color and multi-color assays are disclosed. Further disclosed are universal expression vectors with cassettes that allow the rapid construction of assays for a large and diverse number of gene/reporter combinations. The development of such assays is shown to be straightforward, providing for a broad, flexible and biologically relevant platform for drug discovery.

Protein fragment complementation assays for high-throughput and high-content screening

The present invention describes rapid methods to screen for biomolecular interactions in vivo based on protein fragment complementation assays (PCA). We have demonstrated an in vivo library-versus-library screening strategy that has numerous applications in the identification of novel protein-protein interactions and in directed evolution. Also we demonstrate the detection of protein-protein interactions starting with defined (full-length) cDNAs, and the concomitant generation of functional assays that provide initial validation of the cDNA products as being biologically relevant. Also, we screened a large cDNA collection using automated PCA, combined with quantitative detection of protein-protein complexes. The invention enables bait-vs.-library, library-vs.-library and defined gene screening in any type of cell or cellular context, and using a wide range of reporters and detection methods. The invention allows for identifying and validating genes involved in any cellular process and also provide assays to study effects of potential drugs, or gene knockouts on specific pathways.

In vivo screening of protein-protein interactions with protein-fragment complementation assays

The present invention is directed to Protein-fragment Complementation Assays (PCAs) and assay compositions based on fluorescent proteins. The invention provides methods for fragmenting fluorescent proteins and generating mutant fragments with desired spectral characteristics for PCA. The invention encompasses assays and compositions based on fluorescent proteins from the species Aequorea, Anemonia and Anthozoa. In particular, the invention is directed to fragments of mutant fluorescent proteins having improved spectral properties over the wild-type proteins. The invention encompasses fragments of mutant versions ofgreen fluorescent protein (GFP), in particular yellow fluorescent proteins (EYFP and super-EYFP), 'Venus', cyan, 'citrine', blue, cyan-green, and photoactivatable variants of GFP.

The present invention provides protein single-color and multi-color protein fragment complementation assays for drug discovery, in particular to identify compounds that activate or inhibit cellular pathways. Based on the selection of an interacting protein pair combined with an appropriate PCA reporter such as monomeric enzymes and fluorescent proteins, the assays may be run in high-throughput or high-content mode and may be used in automated screening of libraries of compounds. Methods are described for constructing such assays for one or more steps in a biochemical pathway; testing the effects of compounds from combinatorial, natural product, peptide, antibody, nucleic acid or other diverse libraries on the protein or pathway(s) of interest; and using the results of the screening to identify specific compounds that activate or inhibit the protein or pathway(s) of interest. The development of such assays provides for a broad, flexible and biologically relevant platform for drug discovery.

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Livermore, CA, United States of America

Jane Lamerdin