Ebp1, an ErbB‐3 binding protein, interacts with Rb and affects Rb transcriptional regulation

@article{Xia2001Ebp1AE,
  title={Ebp1, an ErbB‐3 binding protein, interacts with Rb and affects Rb transcriptional regulation},
  author={Xianmin Xia and Aiwu Cheng and Tracy J. Lessor and Yuexing Zhang and Anne W. Hamburger},
  journal={Journal of Cellular Physiology},
  year={2001},
  volume={187}
}
Ebp1, an ErbB‐3 binding protein, inhibits the proliferation and induces the differentiation of human breast cancer cells. The mechanisms of these effects are unknown. Rb, the product of the retinoblastoma gene, is an important modulator of cell cycle progression and cellular differentiation. We report that Rb is a binding target for Ebp1. Ebp1 was localized to both the nucleus and the cytoplasm of logarithmically growing AU565 breast cancer cells and HeLa cells as determined by confocal… 

Repression of E2F1-mediated transcription by the ErbB3 binding protein Ebp1 involves histone deacetylases.

It is shown here that Ebp1 can inhibit the transcription of other E2F-regulated reporter genes and of several endogenous E2f-regulated genes important in cell cycle progression in both Rb positive and Rb null cells.

Phosphorylation of the ErbB3 binding protein Ebp1 by p21-activated kinase 1 in breast cancer cells

It is demonstrated for the first time that Ebp1 is a substrate of PAK1 and the importance of thePAK1 phosphorylation site for the functional activity of Ebp 1 in breast cancer cells is demonstrated.

The ErbB3 binding protein Ebp1 interacts with Sin3A to repress E2F1 and AR-mediated transcription

Results demonstrate that Ebp1 participates in transcriptional regulation via its interaction with the Sin3–HDAC and Chromatin immunoprecipitation and DNA affinity precipitation analysis demonstrated that Eb p1 and Sin3A associate at the PSA and E2F1 promoters.

Specificity and heregulin regulation of Ebp1 (ErbB3 binding protein 1) mediated repression of androgen receptor signalling

It is suggested that Ebp1 is an AR corepressor whose biological activity can be regulated by the ErbB3/4 ligand, HRG, and this study demonstrates that Eb p1 repressed transcriptional activation of wild-type AR in prostate cancer cell lines.

Heregulin Regulates the Ability of the ErbB3-binding Protein Ebp1 to Bind E2F Promoter Elements and Repress E2F-mediated Transcription*

These findings suggest that Ebp1, by linking HRG activation of membrane receptors to E2F gene activity, may be a downstream modulator of the effects of HRG on cell cycle progression.

Ebp1-mediated inhibition of cell growth requires serine 363 phosphorylation.

It is shown that serine 363 (S363) of Ebp1 is phosphorylated in vivo, and the importance of S363 phosphorylation in the function of Eb p1 is indicated.

The ErbB3-binding protein Ebp1 suppresses androgen receptor-mediated gene transcription and tumorigenesis of prostate cancer cells.

Ebp1 is a previously unrecognized therapeutic target for treatment of hormone refractory prostate cancer and down-regulates expression of AR and AR-regulated genes in the LNCaP prostate cancer cell line.

Repression of androgen receptor mediated transcription by the ErbB-3 binding protein, Ebp1

Ebp1 may play a role in the function of the AR and provide a link between ErbB receptors and the AR, and this binding was increased by androgen treatment.

Opposing roles of the two isoforms of ErbB3 binding protein 1 in human cancer cells

The aim of the current review is to provide a summary on distinctive cellular functions of two Ebp1 proteins and their molecular partners that might be responsible for the unique functions of each isoform of Ebp 1.
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