title: A high-throughput assay for signal transducer and activator of transcription 5b based on fluorescence polarization.
abstract: Signal transducer and activator of transcription 5b (STAT5b) is constitutively activated in many human tumors. Activity of STAT5b requires binding of its Src homology 2 (SH2) domain to certain phosphotyrosine-containing sequences. We have developed a high-throughput assay based on fluorescence polarization that allows screening of chemical libraries for compounds that inhibit STAT5b by interfering with the function of its SH2 domain. The assay, which is based on binding between a fluorescein-labeled phosphotyrosine peptide derived from the erythropoietin receptor to the STAT5b SH2 domain, is stable with regard to dimethyl sulfoxide concentration and time and has a Z' value of 0.66+/-0.11 in a 384-well format.
authors.affiliation: Max Planck Institute of Biochemistry, Department of Molecular Biology, and Munich Center for Integrated Protein Science (CIPSM), Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Judith
authors.initials: J
authors.lastname: Müller
authors.forename: Jochen
authors.initials: J
authors.lastname: Schust
authors.forename: Thorsten
authors.initials: T
authors.lastname: Berg
mesh_terms: D000595:Amino Acid Sequence; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D005454:Fluorescence Polarization / Q000379:methods*; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D050799:STAT5 Transcription Factor / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism*; D054852:Small Molecule Libraries / Q000494:pharmacology*; D012965:Sodium Chloride / Q000494:pharmacology; D018909:src Homology Domains
chemical_list: D005456:Fluorescent Dyes; D050799:STAT5 Transcription Factor; C494095:STAT5B protein, human; D054852:Small Molecule Libraries; D012965:Sodium Chloride; D004121:Dimethyl Sulfoxide