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Your search keyword '"Ye QN"' showing total 3 results
Start Over Author "Ye QN" Topic dna-binding proteins
3 results on '"Ye QN"'

1. [XBP-1 interacts with estrogen receptor alpha (ERalpha)].

Author

Ding LH, Ye QN, Yan JH, Zhu JH, Lü QJ, Wang ZH, and Huang CF

Subjects
Breast Neoplasms genetics, Cell Line, Tumor, DNA-Binding Proteins genetics, Estrogen Receptor alpha genetics, Female, Humans, RNA, Messenger biosynthesis, RNA, Messenger genetics, Regulatory Factor X Transcription Factors, Signal Transduction, Transcription Factors genetics, X-Box Binding Protein 1, Breast Neoplasms metabolism, DNA-Binding Proteins metabolism, Estrogen Receptor alpha metabolism, Protein Interaction Domains and Motifs physiology, Transcription Factors metabolism
Abstract

Estrogen receptor alpha (ERalpha) has been a primary target of treatment as well as a prognostic indicator for breast cancer. The level of human X-box binding protein 1 (XBP-1) mRNA was related with that of ERalpha in breast tumors and was over-expressed in some breast tumors. These previous studies suggested that XBP-1 may interact with ERalpha. XBP-1 has two isoforms, XBP-1S and XBP-1U, as the result of unique splicing. GST pull-down assay showed that both XBP-1S and XBP-1U bound to ERalpha in vitro. The binding of XBP-1S to ERalpha was stronger than that of XBP-1U to ERalpha. Co-immunoprecipitation revealed that the binding was in a ligand-independent manner. XBP-1S and XBP-1U interacted with the region of ERalpha that contains a DNA-binding domain. The ERalpha-interacting regions on XBP-1S and XBP-1U have been mapped to two regions, the N-terminal basic region leucine zipper domain (bzip) and the C-terminal activation domain. These findings suggest that XBP-1S and XBP-1U may participate in ERalpha signaling pathway through the mediation of ERalpha.

Published
2004

2. [Expression of XBP-1 in breast cancer cell lines and its role in ERalpha signaling].

Author

Ding LH, Ye QN, Lu QJ, Zhu JH, Yan JH, Wang ZH, and Huang CF

Subjects
Breast Neoplasms metabolism, Cell Line, Tumor, DNA-Binding Proteins genetics, Estrogen Receptor alpha, Female, Humans, RNA, Messenger analysis, Regulatory Factor X Transcription Factors, Response Elements physiology, Transcription Factors genetics, X-Box Binding Protein 1, Breast Neoplasms pathology, DNA-Binding Proteins physiology, Receptors, Estrogen physiology, Signal Transduction physiology, Transcription Factors physiology
Abstract

Estrogen receptor (ERalpha) plays an important role in the development and progression of breast cancer. Several recent studies have demonstrated that expression of human X-box binding protein 1 (XBP-1) is associated with ERalpha status in breast tumors and overexpressed in a subset of breast tumors. XBP-1 has two splicing variants, which were designated as XBP-1S and XBP-1U, respectively. However, little is known about the expression pattern of XBP-1S and XBP-1U in breast cancer cells and about their roles in ERalpha signaling. In this study, the expression of two splicing forms of XBP-1 was detected in breast cancer cell lines with RT-PCR. Estrogen response element (ERE) -containing luciferase reporter assay was used to determine the effects of XBP-1S and XBP-1U on the transcription activity of ERalpha in MDA-MB-435 breast cancer cells. The result showed that both XBP-1S and XBP-1U enhanced the transcription activity of ERalpha in a hormone-independent and dose-dependent manner and the activity of of XBP-1S is higher than that of XBP-1U. Enhancement of ERE-containing luciferase reporter gene expression by XBP-1S and XBP-1U was dependent on ERalpha. These data suggest that XBP-1S and XBP-1U may play important roles in breast cancer growth and progression through ERalpha signaling.

Published
2004

3. [XBP-1 enhances the transcriptional activity of estrogen receptor alpha].

Author

Ding LH, Ye QN, Zhu JH, Yan JH, Zhong HJ, Wang ZH, and Huang CF

Subjects
Alternative Splicing, Blotting, Western, Cell Line, Cell Line, Tumor, DNA-Binding Proteins genetics, Estrogen Receptor alpha, Glutathione Transferase genetics, Glutathione Transferase metabolism, Humans, Luciferases genetics, Luciferases metabolism, Plasmids genetics, Protein Binding, Protein Isoforms genetics, Protein Isoforms metabolism, Receptors, Estrogen genetics, Regulatory Factor X Transcription Factors, Transcription Factors genetics, Transfection, Up-Regulation, X-Box Binding Protein 1, DNA-Binding Proteins metabolism, Receptors, Estrogen metabolism, Transcription Factors metabolism
Abstract

The estrogen receptor (ERalpha) is a member of a large superfamily of nuclear receptors that regulates the transcription of estrogen-responsive genes. Several recent studies have demonstrated that human X-box binding protein 1 (XBP-1) mRNA expression is associated with ERalpha status in breast tumors. More recently, two forms of XBP-1 were identified due to their unique splicing. The two splicing variants of XBP-1 were designated XBP-1S and XBP-1U, respectively. In this study, the coding sequences of XBP-1S and XBP-1U were cloned respectively into the expression vector pcDNA3 harboring FLAG epitope, generating the recombinant plasmids pcDNA3-FLAG-XBP-1S and pcDNA3-FLAG-XBP-1U. Western blot analysis showed that both XBP-1S and XBP-1U were expressed in mammalian cells. To determine the effects of XBP-1S and XBP-1U on the transcriptional activity of ERalpha, MDA-MB-231 breast cancer cells were cotransfected with the expression vectors for ERalpha and either pcDNA3-FLAG-XBP-1S or pcDNA3-FLAG-XBP-1U. The results indicated that XBP-1S and XBP-1U enhanced ERalpha-mediated transcriptional activities in a hormone-independent manner. GST pull-down assay showed that both XBP-1S and XBP-1U interacted with ERalpha. These data suggest that XBP-1S and XBP-1U may play an important role in breast cancer growth and progression through ERalpha signaling.

Published
2003

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