title: A high throughput screening assay system for the identification of small molecule inhibitors of gsp.
abstract: Mis-sense mutations in the α-subunit of the G-protein, Gsα, cause fibrous dysplasia of bone/McCune-Albright syndrome. The biochemical outcome of these mutations is constitutively active Gsα and increased levels of cAMP. The aim of this study was to develop an assay system that would allow the identification of small molecule inhibitors specific for the mutant Gsα protein, the so-called gsp oncogene. Commercially available Chinese hamster ovary cells were stably transfected with either wild-type (WT) or mutant Gsα proteins (R201C and R201H). Stable cell lines with equivalent transfected Gsα protein expression that had relatively lower (WT) or higher (R201C and R201H) cAMP levels were generated. These cell lines were used to develop a fluorescence resonance energy transfer (FRET)-based cAMP assay in 1536-well microplate format for high throughput screening of small molecule libraries. A small molecule library of 343,768 compounds was screened to identify modulators of gsp activity. A total of 1,356 compounds with inhibitory activity were initially identified and reconfirmed when tested in concentration dose responses. Six hundred eighty-six molecules were selected for further analysis after removing cytotoxic compounds and those that were active in forskolin-induced WT cells. These molecules were grouped by potency, efficacy, and structural similarities to yield 22 clusters with more than 5 of structurally similar members and 144 singleton molecules. Seven chemotypes of the major clusters were identified for further testing and analyses.
authors.affiliation: Skeletal Clinical Studies Unit, Craniofacial and Skeletal Diseases Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Nisan
authors.initials: N
authors.lastname: Bhattacharyya
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Xin
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Catherine Z
authors.initials: CZ
authors.lastname: Chen
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Mathews Griner
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: James
authors.initials: J
authors.lastname: Inglese
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Austin
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Marugan
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Noel
authors.initials: N
authors.lastname: Southall
authors.affiliation: Clinical Endocrinology Branch, Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Susanne
authors.initials: S
authors.lastname: Neumann
authors.affiliation: Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: John K
authors.initials: JK
authors.lastname: Northup
authors.affiliation: Department of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Marc
authors.initials: M
authors.lastname: Ferrer
authors.affiliation: Skeletal Clinical Studies Unit, Craniofacial and Skeletal Diseases Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Collins
mesh_terms: D000818:Animals; D016466:CHO Cells; D049109:Cell Proliferation / Q000187:drug effects*; D005576:Colforsin / Q000494:pharmacology; D006224:Cricetinae; D003412:Cricetulus; D000242:Cyclic AMP / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D031541:Fluorescence Resonance Energy Transfer; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans; D050505:Mutant Proteins / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D054852:Small Molecule Libraries / Q000494:pharmacology*; D013379:Substrate Specificity; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D050505:Mutant Proteins; D054852:Small Molecule Libraries; D014665:Vasodilator Agents; D005576:Colforsin; D000242:Cyclic AMP; D019205:GTP-Binding Protein alpha Subunits, Gs