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dc.contributor.authorEvers, B. Mark
dc.contributor.authorWang, Xiaofu
dc.contributor.authorZhou, Zhichao
dc.contributor.authorTownsend, Courtney M.
dc.contributor.authorMcNeil, Gerard P.
dc.contributor.authorDobner, Paul R.
dc.date2022-08-11T08:08:57.000
dc.date.accessioned2022-08-23T16:13:21Z
dc.date.available2022-08-23T16:13:21Z
dc.date.issued1995-07-01
dc.date.submitted2008-09-02
dc.identifier.citation<p>Mol Cell Biol. 1995 Jul;15(7):3870-81.</p>
dc.identifier.issn0270-7306 (Print)
dc.identifier.doi10.1128/MCB.15.7.3870
dc.identifier.pmid7791794
dc.identifier.urihttp://hdl.handle.net/20.500.14038/33601
dc.description.abstractExpression of the gene encoding neurotensin/neuromedin N (NT/N) is mostly limited to the brain and specialized enteroendocrine cells (N cells) of the distal small intestine. We have analyzed the NT/N DNA sequences upstream of the RNA start site that direct cell-specific expression using a novel human endocrine cell line, BON, that resembles intestinal N cells in several important aspects, including NT/N precursor protein processing, ratios of different NT/N mRNA forms, and high levels of constitutive expression of the NT/N gene. Transient transfection assays with plasmids with progressive 5' deletions of the rat NT/N promoter identified the proximal 216 bp of 5' flanking sequences as essential for high-level constitutive NT/N expression in BON cells. In addition, a detailed mutational analysis defined multiple regions within the proximal 216 bp that contribute to cell-specific NT/N expression. These elements include a proximal cyclic AMP response element (CRE)/AP-1-like motif (TGACATCA) that binds c-Jun, JunD, CRE-binding (CREB), and ATF proteins, a near-consensus glucocorticoid response element, and a distal consensus AP-1 site that binds c-Fos, Fra-1, and JunD. In addition, elements contained within two 21-bp imperfect direct repeats play an important role in NT/N expression in BON cells and may bind novel factors that act as positive regulators of NT/N expression. DNase I footprinting and gel shift analyses demonstrate that the sites identified by mutational analysis, and at least one additional site, specifically bind BON cell nuclear proteins in vitro. We speculate that a complex pattern of regulation requiring interaction between a proximal CRE/AP-1-like motif and other upstream control elements play an important role in the high-level constitutive expression of NT/N in the human endocrine cell line BON. In addition, the BON cell line provides a unique model to further characterize the factors regulating cell-specific NT/N expression and to better understand the mechanisms responsible for the terminal differentiation of the N-cell lineage in the gut.
dc.language.isoen_US
dc.relation<p><a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7791794&dopt=Abstract ">Link to article in PubMed</a></p>
dc.relation.urlhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC230627/
dc.subjectActivating Transcription Factor 1; Activating Transcription Factor 2; Adenocarcinoma; Animals; Base Sequence; Binding, Competitive; Cyclic AMP Response Element-Binding Protein; DNA Mutational Analysis; DNA-Binding Proteins; *Gene Expression Regulation, Neoplastic; Humans; Molecular Sequence Data; Neurotensin; Pancreatic Neoplasms; Peptide Fragments; Promoter Regions (Genetics); Protein Binding; Proto-Oncogene Proteins c-fos; Proto-Oncogene Proteins c-jun; Rats; Sequence Deletion; Tissue Distribution; Transcription Factors; Tumor Cells, Cultured
dc.subjectLife Sciences
dc.subjectMedicine and Health Sciences
dc.titleCharacterization of promoter elements required for cell-specific expression of the neurotensin/neuromedin N gene in a human endocrine cell line
dc.typeArticle
dc.source.journaltitleMolecular and cellular biology
dc.source.volume15
dc.source.issue7
dc.identifier.legacycoverpagehttps://escholarship.umassmed.edu/gsbs_sp/270
dc.identifier.contextkey614205
html.description.abstract<p>Expression of the gene encoding neurotensin/neuromedin N (NT/N) is mostly limited to the brain and specialized enteroendocrine cells (N cells) of the distal small intestine. We have analyzed the NT/N DNA sequences upstream of the RNA start site that direct cell-specific expression using a novel human endocrine cell line, BON, that resembles intestinal N cells in several important aspects, including NT/N precursor protein processing, ratios of different NT/N mRNA forms, and high levels of constitutive expression of the NT/N gene. Transient transfection assays with plasmids with progressive 5' deletions of the rat NT/N promoter identified the proximal 216 bp of 5' flanking sequences as essential for high-level constitutive NT/N expression in BON cells. In addition, a detailed mutational analysis defined multiple regions within the proximal 216 bp that contribute to cell-specific NT/N expression. These elements include a proximal cyclic AMP response element (CRE)/AP-1-like motif (TGACATCA) that binds c-Jun, JunD, CRE-binding (CREB), and ATF proteins, a near-consensus glucocorticoid response element, and a distal consensus AP-1 site that binds c-Fos, Fra-1, and JunD. In addition, elements contained within two 21-bp imperfect direct repeats play an important role in NT/N expression in BON cells and may bind novel factors that act as positive regulators of NT/N expression. DNase I footprinting and gel shift analyses demonstrate that the sites identified by mutational analysis, and at least one additional site, specifically bind BON cell nuclear proteins in vitro. We speculate that a complex pattern of regulation requiring interaction between a proximal CRE/AP-1-like motif and other upstream control elements play an important role in the high-level constitutive expression of NT/N in the human endocrine cell line BON. In addition, the BON cell line provides a unique model to further characterize the factors regulating cell-specific NT/N expression and to better understand the mechanisms responsible for the terminal differentiation of the N-cell lineage in the gut.</p>
dc.identifier.submissionpathgsbs_sp/270
dc.contributor.departmentDepartment of Molecular Genetics and Microbiology
dc.contributor.departmentGraduate School of Biomedical Sciences
dc.source.pages3870-81


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