Transcriptional regulation of the major zinc uptake protein hZip1 in prostate cancer cells.
hZip1 has been characterized as the major zinc uptake transporter regulating the accumulation of zinc in prostate cells. The mechanisms regulating expression of hZip1 have not been described. To explore the mechanisms of transcriptional regulation of the hZip1 gene, we determined the putative promoter sequence for hZip1 and identified the potential transcription start site within the predicted hZip1 promoter region. To further characterize the promoter region for basal hZip1 transcription, 3' and 5' deletion constructs and constructs with mutated binding sites for putative transcription factors were generated by PCR amplification and assessed for transcriptional activity with a luciferase reporter assay in PC-3 prostate cancer cells. The ability of the specific transcription factors to bind the hZip1 core promoter was confirmed by EMSA, GelSupershift and ChIP assays. Our experiments identified the core promoter region responsible for constitutive expression of hZip1 and demonstrated critical roles for SP1 and CREB1 in transcriptional regulation of the hZip1 gene in prostate cancer cells.
Makhov
Peter
P
Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA. petr.makhov@fccc.edu
Golovine
Konstantin
K
Uzzo
Robert G
RG
Wuestefeld
Torsten
T
Scoll
Benjamin J
BJ
Kolenko
Vladimir M
VM
D000818:Animals; D001483:Base Sequence; D027682:Cation Transport Proteins / Q000235:genetics*; D045744:Cell Line, Tumor; D019295:Computational Biology; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D011471:Prostatic Neoplasms / Q000235:genetics*; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000378:metabolism; D016415:Sequence Alignment; D016329:Sp1 Transcription Factor / Q000378:metabolism; D024363:Transcription Initiation Site; D014158:Transcription, Genetic; D014162:Transfection; D015032:Zinc / Q000378:metabolism*
C115163:CREB1 protein, human; D027682:Cation Transport Proteins; D017362:Cyclic AMP Response Element-Binding Protein; D034741:RNA, Small Interfering; C403517:SLC39A1 protein, human; D016329:Sp1 Transcription Factor; D015032:Zinc