Patent ID: 7049080

Claim:
An immunoassay for screening modulators of threonine or serine kinase activity comprising: a) providing a threonine or serine kinase substrate protein or peptide comprising the sequence motif -Z-X—Y or —Y—X-Z- wherein Z=threonine or serine X=a sequence of amino acids-in the range of between 1 and 1000 amino acids, which may be the same or different Y=phospho-tyrosine, phospho-threonine or phospho-serine; b) adding a test compound; c) incubating the protein or peptide with a phosphate donor and a threonine or serine kinase under conditions and for a sufficient time to permit phosphorylation of the Z position of the kinase substrate peptide or protein, wherein the kinase substrate may be a labeled or unlabeled compound: d) adding an antibody having a specificity to the kinase substrate peptide or protein which is phosphorylated at the Y and Z positions, wherein the antibody may be a labeled or unlabeled antibody; e) detecting the threonine or serine kinase activity; and f) comparing the threonine or serine kinase activity in the presence of the test compound with the threonine or serine kinase activity in the absence of the test compound, wherein altered threonine or serine kinase activity, detected by either labeled antibody or labeled kinase substrate, in the presence of the test compound relative to threonine or serine kinase activity in the absence of the test compound indicates a modulator of threonine or serine kinase activity.