Isolation and characterization of ARA160 as the first androgen receptor N-terminal-associated coactivator in human prostate cells.
The androgen receptor (AR) is a member of the steroid receptor superfamily that may require coactivators for proper or maximal transactivation. Using a purified AR N-terminal peptide as a probe to screen the human testis expression library, we identified an androgen-enhanced AR N-terminal-associated protein ARA160, which consists of 1,093 amino acids with an apparent molecular mass of 160 kDa. Sequence comparison in GenBank(TM) reveals that ARA160 shares an identical sequence with a HIV-1 TATA element modulatory factor, TMF. The far-Western blotting and co-immunoprecipitation assays demonstrate that the AR can interact directly with ARA160/TMF. Affinity gel pull-down and mammalian two-hybrid assays further suggest androgen can enhance significantly the interaction between AR and ARA160. Transient transfection assays demonstrated that ARA160 might function as a coactivator for AR-mediated transactivation in human prostate cancer PC-3 cells. Our data further suggest that this AR N-terminal coactivator can function cooperatively with AR C-terminal coactivator, ARA70, in PC-3 cells. Together, our data demonstrate that ARA160 might represent the first identified androgen-enhanced N-terminal coactivator for the AR.
Hsiao
P W
PW
Departments of Pathology, Urology, and Radiation Oncology, George Whipple Laboratory for Cancer Research, University of Rochester, Rochester, New York 14642, USA.
Chang
C
C
D000595:Amino Acid Sequence; D000728:Androgens / Q000378:metabolism*; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D008297:Male; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics; D008969:Molecular Sequence Data; D056918:Nuclear Receptor Coactivators; D015513:Oncogene Proteins; D011401:Promoter Regions, Genetic; D011467:Prostate / Q000737:chemistry / Q000378:metabolism*; D017430:Prostate-Specific Antigen / Q000235:genetics; D011485:Protein Binding; D011944:Receptors, Androgen / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000378:metabolism; D020218:Response Elements; D017422:Sequence Analysis, DNA; D020079:Terminal Repeat Sequences; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D015533:Transcriptional Activation
D000728:Androgens; D004268:DNA-Binding Proteins; D008024:Ligands; C111382:NCOA4 protein, human; D056918:Nuclear Receptor Coactivators; D015513:Oncogene Proteins; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; D011965:Receptors, Glucocorticoid; D015534:Trans-Activators; D014157:Transcription Factors; C077335:TMF1 protein, human; D017430:Prostate-Specific Antigen