title: Substitution of arginine for cysteine 643 of the glucocorticoid receptor reduces its steroid-binding affinity and transcriptional activity.
abstract: To investigate the mechanism for glucocorticoid resistance in leukemic cells, we sequenced the coding region of glucocorticoid receptor (GR) gene in ten Japanese leukemic cells. We identified a novel heterozygous mutation (C643R) in the ligand-binding domain in P30/OHK cells. Western blot analysis for COS-7 cells transfected with the wild-type or C643R mutant GR plasmid revealed similar protein expression levels. In the ligand-binding assay, the dissociation constant of the C643R GR was six-fold higher than that of the wild-type GR. Moreover, the C643R GR showed no transcriptional activity in the luciferase reporter assay.
authors.affiliation: Project Team for Pharmacogenetics, National Institute of Health Sciences, 1-18-1, Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan. nagano@nihs.go.jp
authors.forename: Michiyo
authors.initials: M
authors.lastname: Nagano
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Shingo
authors.initials: S
authors.lastname: Niimi
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Fujino
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Nishimura
authors.forename: Norie
authors.initials: N
authors.lastname: Murayama
authors.forename: Seiichi
authors.initials: S
authors.lastname: Ishida
authors.forename: Shogo
authors.initials: S
authors.lastname: Ozawa
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Saito
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Sawada
mesh_terms: D019943:Amino Acid Substitution; D001120:Arginine; D003545:Cysteine; D004252:DNA Mutational Analysis; D003907:Dexamethasone / Q000378:metabolism; D006801:Humans; D007938:Leukemia / Q000235:genetics*; D011485:Protein Binding; D011965:Receptors, Glucocorticoid / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
chemical_list: D011965:Receptors, Glucocorticoid; D003907:Dexamethasone; D001120:Arginine; D003545:Cysteine