High-throughput cell-based screening reveals a role for ZNF131 as a repressor of ERalpha signaling.
BACKGROUND
Estrogen receptor alpha (ERalpha) is a transcription factor whose activity is affected by multiple regulatory cofactors. In an effort to identify the human genes involved in the regulation of ERalpha, we constructed a high-throughput, cell-based, functional screening platform by linking a response element (ERE) with a reporter gene. This allowed the cellular activity of ERalpha, in cells cotransfected with the candidate gene, to be quantified in the presence or absence of its cognate ligand E2.


RESULTS
From a library of 570 human cDNA clones, we identified zinc finger protein 131 (ZNF131) as a repressor of ERalpha mediated transactivation. ZNF131 is a typical member of the BTB/POZ family of transcription factors, and shows both ubiquitous expression and a high degree of sequence conservation. The luciferase reporter gene assay revealed that ZNF131 inhibits ligand-dependent transactivation by ERalpha in a dose-dependent manner. Electrophoretic mobility shift assay clearly demonstrated that the interaction between ZNF131 and ERalpha interrupts or prevents ERalpha binding to the estrogen response element (ERE). In addition, ZNF131 was able to suppress the expression of pS2, an ERalpha target gene.


CONCLUSIONS
We suggest that the functional screening platform we constructed can be applied for high-throughput genomic screening candidate ERalpha-related genes. This in turn may provide new insights into the underlying molecular mechanisms of ERalpha regulation in mammalian cells.
Chinese National Human Genome Center, Beijing 100176, PR China. hanxiaorumeng@126.com
Xiao
X
Han
Jinhai
J
Guo
Weiwei
W
Deng
Chenying
C
Zhang
Peige
P
Du
Taiping
T
Shi
Dalong
D
Ma
D019295:Computational Biology; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D047628:Estrogen Receptor alpha / Q000235:genetics* / Q000378:metabolism; D015723:Gene Library; D006367:HeLa Cells; D006801:Humans; D011485:Protein Binding; D012313:RNA / Q000235:genetics; D020218:Response Elements; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D047628:Estrogen Receptor alpha; C051838:TFF1 protein, human; D014157:Transcription Factors; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins; C519599:ZNF131 protein, human; D012313:RNA