title: Reciprocal recruitment of DRIP/mediator and p160 coactivator complexes in vivo by estrogen receptor.
abstract: Two functionally distinct classes of coactivators are recruited by liganded estrogen receptor, the DRIP/Mediator complex and p160 proteins, although the relative dynamics of recruitment is unclear. Previously, we have shown a direct, estradiol-dependent interaction between the DRIP205 subunit of the DRIP complex and the estrogen receptor (ER) AF2 domain. Here we demonstrate the in vivo recruitment of other endogenous DRIP subunits to ER in response to estradiol treatment in MCF-7 cells. To explore the relationship between DRIP and p160 coactivators, we examined the kinetics of coactivator recruitment to the ER target promoter, pS2, by chromatin immunoprecipitation. We observed a cyclic association and dissociation of coactivators with the promoter, with recruitment of p160s and DRIPs occurring in opposite phases, suggesting an exchange between these coactivator complexes at the target promoter.
authors.affiliation: Cell Biology Program, Memorial Sloan-Kettering Cancer Center, Sloan-Kettering Division, Joan and Sanford I. Weill Graduate School of Medical Sciences of Cornell University, New York, New York 10021, USA.
authors.forename: Darya
authors.initials: D
authors.lastname: Burakov
authors.forename: Linda A
authors.initials: LA
authors.lastname: Crofts
authors.forename: Chao-Pei Betty
authors.initials: CP
authors.lastname: Chang
authors.forename: Leonard P
authors.initials: LP
authors.lastname: Freedman
mesh_terms: D006801:Humans; D007700:Kinetics; D056892:Mediator Complex; D009687:Nuclear Proteins / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors; D014407:Tumor Cells, Cultured
chemical_list: C113182:DRIP, VDR interacting protein complex; C491863:MED4 protein, human; D056892:Mediator Complex; D009687:Nuclear Proteins; D011960:Receptors, Estrogen; D015534:Trans-Activators; D014157:Transcription Factors