title: Concerted activation of ETS protein ER81 by p160 coactivators, the acetyltransferase p300 and the receptor tyrosine kinase HER2/Neu.
abstract: Activator of thyroid and retinoic acid receptor (ACTR) is overexpressed in approximately 60% of primary human breast tumors and belongs to the p160 steroid receptor coactivator family. In this study, we identified a novel interaction partner of ACTR, the ETS transcription factor ER81 that is also heavily implicated in mammary tumor formation. ACTR and related p160 family members (steroid receptor coactivator-1 and glucocorticoid receptor-interacting protein-1 (GRIP-1)) augment ER81-mediated transcription. Although ACTR and GRIP-1 can acetylate ER81, this posttranslational modification of ER81 is not required for its stimulation by ACTR or GRIP-1. In addition, ACTR collaborates with the p300 coactivator, a joint interaction partner of ACTR and ER81, to stimulate ER81 function and the ability of p300 to acetylate ER81 is indispensable for this collaboration. Furthermore, the receptor tyrosine kinase HER2/Neu, an oncoprotein particularly found overexpressed in breast tumors, cooperates with both ACTR and p300 to stimulate ER81-mediated transcription. Thus, oncogenic HER2/Neu and ACTR may synergize to orchestrate mammary tumorigenesis through the dysregulation of the transcription factor ER81 and its target genes.
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: Apollina
authors.initials: A
authors.lastname: Goel
authors.forename: Ralf
authors.initials: R
authors.lastname: Janknecht
mesh_terms: D000123:Acetyltransferases / Q000502:physiology*; D000818:Animals; D001943:Breast Neoplasms / Q000378:metabolism; D002352:Carrier Proteins / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000502:physiology*; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000502:physiology*; D004591:Electrophoresis, Polyacrylamide Gel; D005982:Glutathione Transferase / Q000378:metabolism; D006367:HeLa Cells; D051548:Histone Acetyltransferases; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008954:Models, Biological; D009687:Nuclear Proteins / Q000502:physiology*; D051958:Nuclear Receptor Coactivator 2; D056921:Nuclear Receptor Coactivator 3; D029543:Nucleocytoplasmic Transport Proteins; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D016601:RNA-Binding Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor
chemical_list: D000123:Acetyltransferases; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005982:Glutathione Transferase; D051548:Histone Acetyltransferases; D008156:Luciferases; D009687:Nuclear Proteins; D051958:Nuclear Receptor Coactivator 2; D056921:Nuclear Receptor Coactivator 3; D029543:Nucleocytoplasmic Transport Proteins; D012313:RNA; D016601:RNA-Binding Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D018168:Receptors, Retinoic Acid; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor; C095239:ETV1 protein, human; C490641:Etv1 protein, mouse; C491719:MYBBP1A protein, human; C498001:NCOA2 protein, human