Nuclear receptor interaction protein, a coactivator of androgen receptors (AR), is regulated by AR and Sp1 to feed forward and activate its own gene expression through AR protein stability
| Autor: | Show-Li Chen, Chih-Chiang Wang, Yeou-Ping Tsao, Pei-Hong Chen |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Male
Transcriptional Activation Sp1 Transcription Factor Molecular Sequence Data Biology Cell Line Transcription (biology) Cell Line Tumor Coactivator Genetics Animals Humans Amino Acid Sequence RNA Messenger Nuclear protein Promoter Regions Genetic Molecular Biology Adaptor Proteins Signal Transducing Sp1 transcription factor Binding Sites Base Sequence Nuclear Proteins Prostatic Neoplasms Molecular biology Up-Regulation Androgen receptor Nuclear receptor Receptors Androgen Androgen Response Element Chromatin immunoprecipitation |
| Zdroj: | Nucleic Acids Research |
| ISSN: | 1362-4962 0305-1048 |
| Popis: | Previously, we found a novel gene, nuclear receptor interaction protein (NRIP), a transcription cofactor that can enhance an AR-driven PSA promoter activity in a ligand-dependent manner in prostate cancer cells. Here, we investigated NRIP regulation. We cloned a 413-bp fragment from the transcription initiation site of the NRIP gene that had strong promoter activity, was TATA-less and GC-rich, and, based on DNA sequences, contained one androgen response element (ARE) and three Sp1-binding sites (Sp1-1, Sp1-2, Sp1-3). Transient promoter luciferase assays, chromatin immunoprecipitation and small RNA interference analyses mapped ARE and Sp1-2-binding sites involved in NRIP promoter activation, implying that NRIP is a target gene for AR or Sp1. AR associates with the NRIP promoter through ARE and indirectly through Sp1-binding site via AR–Sp1 complex formation. Thus both ARE and Sp1-binding site within the NRIP promoter can respond to androgen induction. More intriguingly, NRIP plays a feed-forward role enhancing AR-driven NRIP promoter activity via NRIP forming a complex with AR to protect AR protein from proteasome degradation. This is the first demonstration that NRIP is a novel AR-target gene and that NRIP expression feeds forward and activates its own expression through AR protein stability. |
| Databáze: | OpenAIRE |
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