Abstract: Methods and compositions for glycogen synthase kinase 3 assays continue to be required for detection of glycogen synthase 3 kinase, assessment of glycogen synthase 3 kinase activity and identification of modulators of glycogen synthase 3 kinase. Methods and compositions for glycogen synthase kinase 3 assays are provided herein based on the discovery of a previously unknown interaction between glycogen synthase 3 kinase and eukaryotic translation initiation factor 4E-binding protein 1 which serves as a substrate for glycogen synthase kinase 3-alpha and glycogen synthase kinase 3-beta.

Abstract: Tyrosine kinase substrates are described herein that are phosphorylated by many and diverse tyrosine kinases, and are chemically stable relative to co-polymers of poly-EY or poly-EAY having random molecular weights in the range of 20-50 kDa. Tyrosine kinase substrate peptides are provided according to embodiments described herein which include an isolated tyrosine kinase substrate peptide having molecular weight in the range of about 0.5 kD-10 kD. Tyrosine kinase substrate peptides are provided according to embodiments described herein having no more than 50 amino acids. The peptides include 2-25 phosphorylation modules and each phosphorylation module has 2-3 amino acid residues.

Abstract: Methods and compositions for glycogen synthase kinase 3 assays continue to be required for detection of glycogen synthase 3 kinase, assessment of glycogen synthase 3 kinase activity and identification of modulators of glycogen synthase 3 kinase. Methods and compositions for glycogen synthase kinase 3 assays are provided herein based on the discovery of a previously unknown interaction between glycogen synthase 3 kinase and eukaryotic translation initiation factor 4E-binding protein 1 which serves as a substrate for glycogen synthase kinase 3-alpha and glycogen synthase kinase 3-beta.

Abstract: Tyrosine kinase substrates are described herein that are phosphorylated by many and diverse tyrosine kinases, and are chemically stable relative to co-polymers of poly-EY or poly-EAY having random molecular weights in the range of 20-50 kDa. Tyrosine kinase substrate peptides are provided according to embodiments described herein which include an isolated tyrosine kinase substrate peptide having molecular weight in the range of about 0.5 kD-10 kD. Tyrosine kinase substrate peptides are provided according to embodiments described herein having no more than 50 amino acids. The peptides include 2-25 phosphorylation modules and each phosphorylation module has 2-3 amino acid residues.

Abstract: A medium for a scintillation assay includes a fluorescent Coumarin dye, typically having a Stokes shift of at least 50 nm and a fluorescence in the range of 460-500 nm. The composition may further include secondary scintillator materials which as PPO, DPA, bis-MSB, BiBuQ, and the like. The scintillator medium may be a liquid medium or a solid medium. Also disclosed is an assay utilizing the material of the present invention, as well as a specifically solid-state scintillator medium incorporating Coumarin 153 and BiBuQ.