ERBP, a novel estrogen receptor binding protein enhancing the activity of estrogen receptor.
To understand the mechanism by which estrogen receptor (ER) activates transcription in a tissue specific fashion, we isolated ERalpha binding protein (ERBP) by performing yeast two-hybrid screening with human mammary gland cDNA library. ERBP is a nuclear protein and its mRNA is ubiquitously expressed. The in vitro interaction of ERBP with ERalpha was demonstrated by GST pull-down assay and this interaction was enhanced by estrogen. In addition, ERBP also bound to PPARgamma, RXRalpha, and ERbeta. ERBP interacted with the DNA binding domain and the hinge region of ERalpha. There are two ERalpha binding regions on ERBP. The binding of ERBP region at C-terminus to ERalpha is increased by estrogen while the binding of ERBP region at N-terminus is not affected by estrogen. The interaction of ERBP with ERalpha was further confirmed in vivo by immunoprecipitation. Transient transfection experiment demonstrated that ERBP enhanced the transcriptional activity of ERalpha.
Bu
Hengfu
H
Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
Kashireddy
Papreddy
P
Chang
Jeffrey
J
Zhu
Yiwei Tony
YT
Zhang
Zhongyi
Z
Zheng
Wei
W
Rao
Sambasiva M
SM
Zhu
Yi-Jun
YJ
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D047628:Estrogen Receptor alpha; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D000077297:Pregnane X Receptor; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000096:biosynthesis; D016601:RNA-Binding Proteins; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D011960:Receptors, Estrogen / Q000737:chemistry / Q000378:metabolism*; D011987:Receptors, Steroid / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C484899:DNTTIP2 protein, human; D047628:Estrogen Receptor alpha; D009687:Nuclear Proteins; D000077297:Pregnane X Receptor; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D011960:Receptors, Estrogen; D011987:Receptors, Steroid; D011994:Recombinant Proteins; D014157:Transcription Factors