title: Gαo potentiates estrogen receptor α activity via the ERK signaling pathway.
abstract: The estrogen receptor α (ERα) is a transcription factor that mediates the biological effects of 17β-estradiol (E(2)). ERα transcriptional activity is also regulated by cytoplasmic signaling cascades. Here, several Gα protein subunits were tested for their ability to regulate ERα activity. Reporter assays revealed that overexpression of a constitutively active Gα(o) protein subunit potentiated ERα activity in the absence and presence of E(2). Transient transfection of the human breast cancer cell line MCF-7 showed that Gα(o) augments the transcription of several ERα-regulated genes. Western blots of HEK293T cells transfected with ER±Gα(o) revealed that Gα(o) stimulated phosphorylation of ERK 1/2 and subsequently increased the phosphorylation of ERα on serine 118. In summary, our results show that Gα(o), through activation of the MAPK pathway, plays a role in the regulation of ERα activity.
authors.affiliation: Section of Hematology and Medical Oncology, Department of Medicine, Tulane University, 1430 Tulane Avenue, SL-78, New Orleans, Louisiana 70112, USA.
authors.forename: Melyssa R
authors.initials: MR
authors.lastname: Bratton
authors.forename: James W
authors.initials: JW
authors.lastname: Antoon
authors.forename: Bich N
authors.initials: BN
authors.lastname: Duong
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Frigo
authors.forename: Syreeta
authors.initials: S
authors.lastname: Tilghman
authors.forename: Bridgette M
authors.initials: BM
authors.lastname: Collins-Burow
authors.forename: Steven
authors.initials: S
authors.lastname: Elliott
authors.forename: Yan
authors.initials: Y
authors.lastname: Tang
authors.forename: Lilia I
authors.initials: LI
authors.lastname: Melnik
authors.forename: Ling
authors.initials: L
authors.lastname: Lai
authors.forename: Jawed
authors.initials: J
authors.lastname: Alam
authors.forename: Barbara S
authors.initials: BS
authors.lastname: Beckman
authors.forename: Steven M
authors.initials: SM
authors.lastname: Hill
authors.forename: Brian G
authors.initials: BG
authors.lastname: Rowan
authors.forename: John A
authors.initials: JA
authors.lastname: McLachlan
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Burow
mesh_terms: D015153:Blotting, Western; D045744:Cell Line, Tumor; D004958:Estradiol / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D057809:HEK293 Cells; D006801:Humans; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000235:genetics / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D010766:Phosphorylation / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012694:Serine / Q000235:genetics / Q000378:metabolism; D014162:Transfection
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D012694:Serine; D004958:Estradiol; D048049:Extracellular Signal-Regulated MAP Kinases; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D019206:GTP-Binding Protein alpha Subunits, Gi-Go