Insulin gene expression in nonexpressing cells appears to be regulated by multiple distinct negative-acting control elements.

Selective transcription of the insulin gene in pancreatic beta cells is regulated by its enhancer, located between nucleotides -340 and -91 relative to the transcription start site. Transcription from the enhancer is controlled by both positive- and negative-acting cellular factors. Cell-type-specific expression is mediated principally by a single cis-acting enhancer element located between -100 and -91 in the rat insulin II gene (referred to as the insulin control element [ICE]), which is acted upon by both of these cellular activities. Analysis of the effect of 5' deletions within the insulin enhancer has identified a region between nucleotides -217 and -197 that is also a site of negative control. Deletion of these sequences from the 5' end of the enhancer leads to transcription of the enhancer in non-insulin-producing cells, even though the ICE is intact. Derepression of this ICE-mediated effect was shown to be due to the binding of a ubiquitously distributed cellular factor to a sequence element which resides just upstream of the ICE (i.e., between nucleotides -110 and -100). We discuss the possible relationship of these results to cell-type-specific regulation of the insulin gene.

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Glucose-induced transcription of the insulin gene is mediated by factors required for beta-cell-type-specific expression

Molecular and Cellular Biology ◽

10.1128/mcb.14.2.871-879.1994 ◽

1994 ◽

Vol 14 (2) ◽

pp. 871-879

Author(s):

A Sharma ◽

R Stein

Keyword(s):

Beta Cell ◽

Insulin Gene ◽

Control Element ◽

Cell Type ◽

Specific Expression ◽

Cis Acting ◽

Cell Extracts ◽

Cell Type Specific Expression ◽

Cell Type Specific

The insulin gene is expressed exclusively in pancreatic islet beta cells. The principal regulator of insulin gene transcription in the islet is the concentration of circulating glucose. Previous studies have demonstrated that transcription is regulated by the binding of trans-acting factors to specific cis-acting sequences within the 5'-flanking region of the insulin gene. To identify the cis-acting control elements within the rat insulin II gene that are responsible for regulating glucose-stimulated expression in the beta cell, we analyzed the effect of glucose on the in vivo expression of a series of transfected 5'-flanking deletion mutant constructs. We demonstrate that glucose-induced transcription of the rat insulin II gene is mediated by sequences located between -126 and -91 bp relative to the transcription start site. This region contains two cis-acting elements that are essential for directing pancreatic beta-cell-type-specific expression of the rat insulin II gene, the insulin control element (ICE; -100 to -91 bp) and RIPE3b1 (-115 to -107 bp). The gel mobility shift assay was used to determine whether the formation of the ICE- and RIPE3b1-specific factor-DNA element complexes were affected in glucose-treated beta-cell extracts. We found that RIPE3b1 binding activity was selectively induced by about eightfold. In contrast, binding to other insulin cis-acting element sequences like the ICE and RIPE3a2 (-108 to -99 bp) were unaffected by these conditions. The RIPE3b1 binding complex was shown to be distinct from the glucose-inducible factor that binds to an element located between -227 to -206 bp of the human and rat insulin I genes (D. Melloul, Y. Ben-Neriah, and E. Cerasi, Proc. Natl. Acad. Sci. USA 90:3865-3869, 1993). We have also shown that mannose, a sugar that can be metabolized by the beta cell, mimics the effects of glucose in the in vivo transfection assays and the in vitro RIPE3b1 binding assays. These results suggested that the RIPE3b1 transcription factor is a primary regulator of glucose-mediated transcription of the insulin gene. However, we found that mutations in either the ICE or the RIPE3b1 element reduced glucose-responsive expression from transfected 5'-flanking rat insulin II gene constructs. We therefore conclude that glucose-regulated transcription of the insulin gene is mediated by cis-acting elements required for beta-cell-type-specific expression.

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Glucose-induced transcription of the insulin gene is mediated by factors required for beta-cell-type-specific expression.

Molecular and Cellular Biology ◽

10.1128/mcb.14.2.871 ◽

1994 ◽

Vol 14 (2) ◽

pp. 871-879 ◽

Cited By ~ 89

Author(s):

A Sharma ◽

R Stein

Keyword(s):

Beta Cell ◽

Insulin Gene ◽

Control Element ◽

Cell Type ◽

Specific Expression ◽

Cis Acting ◽

Cell Extracts ◽

Cell Type Specific Expression ◽

Cell Type Specific

The insulin gene is expressed exclusively in pancreatic islet beta cells. The principal regulator of insulin gene transcription in the islet is the concentration of circulating glucose. Previous studies have demonstrated that transcription is regulated by the binding of trans-acting factors to specific cis-acting sequences within the 5'-flanking region of the insulin gene. To identify the cis-acting control elements within the rat insulin II gene that are responsible for regulating glucose-stimulated expression in the beta cell, we analyzed the effect of glucose on the in vivo expression of a series of transfected 5'-flanking deletion mutant constructs. We demonstrate that glucose-induced transcription of the rat insulin II gene is mediated by sequences located between -126 and -91 bp relative to the transcription start site. This region contains two cis-acting elements that are essential for directing pancreatic beta-cell-type-specific expression of the rat insulin II gene, the insulin control element (ICE; -100 to -91 bp) and RIPE3b1 (-115 to -107 bp). The gel mobility shift assay was used to determine whether the formation of the ICE- and RIPE3b1-specific factor-DNA element complexes were affected in glucose-treated beta-cell extracts. We found that RIPE3b1 binding activity was selectively induced by about eightfold. In contrast, binding to other insulin cis-acting element sequences like the ICE and RIPE3a2 (-108 to -99 bp) were unaffected by these conditions. The RIPE3b1 binding complex was shown to be distinct from the glucose-inducible factor that binds to an element located between -227 to -206 bp of the human and rat insulin I genes (D. Melloul, Y. Ben-Neriah, and E. Cerasi, Proc. Natl. Acad. Sci. USA 90:3865-3869, 1993). We have also shown that mannose, a sugar that can be metabolized by the beta cell, mimics the effects of glucose in the in vivo transfection assays and the in vitro RIPE3b1 binding assays. These results suggested that the RIPE3b1 transcription factor is a primary regulator of glucose-mediated transcription of the insulin gene. However, we found that mutations in either the ICE or the RIPE3b1 element reduced glucose-responsive expression from transfected 5'-flanking rat insulin II gene constructs. We therefore conclude that glucose-regulated transcription of the insulin gene is mediated by cis-acting elements required for beta-cell-type-specific expression.

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Pancreatic beta-cell-type-specific expression of the rat insulin II gene is controlled by positive and negative cellular transcriptional elements.

Molecular and Cellular Biology ◽

10.1128/mcb.9.8.3253 ◽

1989 ◽

Vol 9 (8) ◽

pp. 3253-3259 ◽

Cited By ~ 66

Author(s):

J Whelan ◽

D Poon ◽

P A Weil ◽

R Stein

Keyword(s):

Transcription Factors ◽

Beta Cell ◽

Beta Cells ◽

Pancreatic Beta Cells ◽

Pancreatic Beta Cell ◽

Cell Type ◽

Specific Expression ◽

Cis Acting ◽

Cell Type Specific Expression ◽

Cell Type Specific

The insulin gene is expressed almost exclusively in pancreatic beta-cells. The DNA sequences that control cell-specific expression are located upstream of the transcription initiation site. To identify the cis-acting transcriptional control regions within the rat insulin II gene that are responsible for this tissue-specific expression pattern, we constructed a series of 5'-flanking deletion mutants and analyzed their expression in vivo in transfected insulin-producing and -nonproducing cell lines. Pancreatic beta-cell-specific expression was shown to be controlled by enhancer sequences lying between nucleotides -342 and -91 relative to the transcription start site. The rat insulin II enhancer appears to be a chimera, composed of a number of distinct cis-acting DNA elements. Both positive and negative transcriptional regulatory elements appear to be responsible for this cell-type-specific expression. We have shown that expression from one element within the enhancer, which is found between nucleotides -100 and -91, is regulated by both positive- and negative-acting cellular transcription factors. Expression from chimeras containing only the enhancer element sequences from -100 to -91 were active only in insulin-producing cells, indicating that the positive-acting factor(s) required for this activity may be active only in beta-cells. In contrast to the enhancer region, the rat insulin II gene promoter did not appear to require cell-specific transcription factors. Promoter mutants with 5'-flanking sequences extending to nucleotides -90 and -73 were constitutively active in both insulin-producing and -nonproducing cells. These results suggest that rat insulin II gene transcription in pancreatic beta-cells is imparted by a combination of both negative- and positive-acting cellular factors interacting with the gene enhancer.

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Pancreatic beta-cell-type-specific expression of the rat insulin II gene is controlled by positive and negative cellular transcriptional elements

Molecular and Cellular Biology ◽

10.1128/mcb.9.8.3253-3259.1989 ◽

1989 ◽

Vol 9 (8) ◽

pp. 3253-3259

Author(s):

J Whelan ◽

D Poon ◽

P A Weil ◽

R Stein

Keyword(s):

Transcription Factors ◽

Beta Cell ◽

Beta Cells ◽

Pancreatic Beta Cells ◽

Pancreatic Beta Cell ◽

Cell Type ◽

Specific Expression ◽

Cis Acting ◽

Cell Type Specific Expression ◽

Cell Type Specific

The insulin gene is expressed almost exclusively in pancreatic beta-cells. The DNA sequences that control cell-specific expression are located upstream of the transcription initiation site. To identify the cis-acting transcriptional control regions within the rat insulin II gene that are responsible for this tissue-specific expression pattern, we constructed a series of 5'-flanking deletion mutants and analyzed their expression in vivo in transfected insulin-producing and -nonproducing cell lines. Pancreatic beta-cell-specific expression was shown to be controlled by enhancer sequences lying between nucleotides -342 and -91 relative to the transcription start site. The rat insulin II enhancer appears to be a chimera, composed of a number of distinct cis-acting DNA elements. Both positive and negative transcriptional regulatory elements appear to be responsible for this cell-type-specific expression. We have shown that expression from one element within the enhancer, which is found between nucleotides -100 and -91, is regulated by both positive- and negative-acting cellular transcription factors. Expression from chimeras containing only the enhancer element sequences from -100 to -91 were active only in insulin-producing cells, indicating that the positive-acting factor(s) required for this activity may be active only in beta-cells. In contrast to the enhancer region, the rat insulin II gene promoter did not appear to require cell-specific transcription factors. Promoter mutants with 5'-flanking sequences extending to nucleotides -90 and -73 were constitutively active in both insulin-producing and -nonproducing cells. These results suggest that rat insulin II gene transcription in pancreatic beta-cells is imparted by a combination of both negative- and positive-acting cellular factors interacting with the gene enhancer.

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Pancreatic beta-cell-type-specific transcription of the insulin gene is mediated by basic helix-loop-helix DNA-binding proteins

Molecular and Cellular Biology ◽

10.1128/mcb.11.3.1734-1738.1991 ◽

1991 ◽

Vol 11 (3) ◽

pp. 1734-1738 ◽

Cited By ~ 1

Author(s):

S R Cordle ◽

E Henderson ◽

H Masuoka ◽

P A Weil ◽

R Stein

Keyword(s):

Dna Binding ◽

Beta Cell ◽

Pancreatic Beta Cell ◽

Insulin Gene ◽

Cell Type ◽

Specific Expression ◽

Cis Acting ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

Cell Type Specific

The pancreatic beta-cell-specific expression of the insulin gene is mediated, at least in part, by the interaction of unique trans-acting beta-cell factors with a cis-acting DNA element found within the insulin enhancer (5'-GC CATCTG-3'; referred to as the insulin control element [ICE]) present in the rat insulin II gene between positions -100 and -91. This sequence element contains the consensus binding site for a group of DNA-binding transcription factors called basic helix-loop-helix proteins (B-HLH). As a consequence of the similarity of the ICE with the DNA sequence motif associated with the cis-acting elements of the B-HLH class of binding proteins (CANNTG), the ability of this class of proteins to regulate cell-type-specific expression of the insulin gene was addressed. Cotransfection experiments indicated that overexpression of Id, a negative regulator of B-HLH protein function, inhibits ICE-mediated activity. Antibody to the E12/E47 B-HLH proteins attenuated the formation, in vitro, of a previously described (J. Whelan, S. R. Cordle, E. Henderson, P. A. Weil, and R. Stein, Mol. Cell. Biol. 10:1564-1572, 1990) beta-cell-specific activator factor(s)-ICE DNA complex. Both of these B-HLH proteins (E12 and E47) bound efficiently and specifically to the ICE sequences. The role of B-HLH proteins in mediating pancreatic beta-cell-specific transcription of the insulin gene is discussed.

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Pancreatic beta-cell-type-specific transcription of the insulin gene is mediated by basic helix-loop-helix DNA-binding proteins.

Molecular and Cellular Biology ◽

10.1128/mcb.11.3.1734 ◽

1991 ◽

Vol 11 (3) ◽

pp. 1734-1738 ◽

Cited By ~ 80

Author(s):

S R Cordle ◽

E Henderson ◽

H Masuoka ◽

P A Weil ◽

R Stein

Keyword(s):

Dna Binding ◽

Beta Cell ◽

Pancreatic Beta Cell ◽

Insulin Gene ◽

Cell Type ◽

Specific Expression ◽

Cis Acting ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

Cell Type Specific

The pancreatic beta-cell-specific expression of the insulin gene is mediated, at least in part, by the interaction of unique trans-acting beta-cell factors with a cis-acting DNA element found within the insulin enhancer (5'-GC CATCTG-3'; referred to as the insulin control element [ICE]) present in the rat insulin II gene between positions -100 and -91. This sequence element contains the consensus binding site for a group of DNA-binding transcription factors called basic helix-loop-helix proteins (B-HLH). As a consequence of the similarity of the ICE with the DNA sequence motif associated with the cis-acting elements of the B-HLH class of binding proteins (CANNTG), the ability of this class of proteins to regulate cell-type-specific expression of the insulin gene was addressed. Cotransfection experiments indicated that overexpression of Id, a negative regulator of B-HLH protein function, inhibits ICE-mediated activity. Antibody to the E12/E47 B-HLH proteins attenuated the formation, in vitro, of a previously described (J. Whelan, S. R. Cordle, E. Henderson, P. A. Weil, and R. Stein, Mol. Cell. Biol. 10:1564-1572, 1990) beta-cell-specific activator factor(s)-ICE DNA complex. Both of these B-HLH proteins (E12 and E47) bound efficiently and specifically to the ICE sequences. The role of B-HLH proteins in mediating pancreatic beta-cell-specific transcription of the insulin gene is discussed.

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Cell-specific expression of ENACα gene by FOXA1 in the glucocorticoid receptor pathway

International Journal of Immunopathology and Pharmacology ◽

10.1177/2058738420946192 ◽

2020 ◽

Vol 34 ◽

pp. 205873842094619 ◽

Cited By ~ 1

Author(s):

Young Sun Chung ◽

Hong Lan Jin ◽

Kwang Won Jeong

Keyword(s):

Gene Expression ◽

Glucocorticoid Receptor ◽

Molecular Mechanisms ◽

Regulation Of Gene Expression ◽

A549 Cells ◽

Rna Seq ◽

Cell Type ◽

Specific Expression ◽

Cell Type Specific ◽

Specific Regulation

Introduction: The glucocorticoid receptor (GR) is one of the most widely studied ligand-dependent nuclear receptors. The combination of transcriptional regulatory factors required for the expression of individual genes targeted by GR varies across cell types; however, the mechanisms underlying this cell type–specific regulation of gene expression are not yet clear. Methods: Here, we investigated genes regulated by GR in two different cell lines, A549 and ARPE-19, and examined how gene expression varied according to the effect of pioneer factors using RNA-seq and RT-qPCR. Results: Our RNA-seq results identified 19 and 63 genes regulated by GR that are ARPE-19-specific and A549-specific, respectively, suggesting that GR induces the expression of different sets of genes in a cell type–specific manner. RT-qPCR confirmed that the epithelial sodium channel ( ENACα) gene is an ARPE-19 cell-specific GR target gene, whereas the FK506 binding protein 5 ( FKBP5) gene was A549 cell-specific. There was a significant decrease in ENACα expression in FOXA1-deficient ARPE-19 cells, suggesting that FOXA1 might function as a pioneer factor enabling the selective expression of ENACα in ARPE-19 cells but not in A549 cells. Conclusion: These findings indicate that ENACα expression in ARPE-19 cells is regulated by FOXA1 and provide insights into the molecular mechanisms of cell type–specific expression of GR-regulated genes.

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CRISPR/Cas9-based Editing of a Sensitive Transcriptional Regulatory Element to Achieve Cell Type-Specific Knockdown of the NEMO Scaffold Protein

10.1101/450320 ◽

2018 ◽

Cited By ~ 1

Author(s):

Milad Babaei ◽

Yuekun Liu ◽

Shelly M. Wuerzberger-Davis ◽

Alan T. Yeo ◽

Larisa Kagermazova ◽

...

Keyword(s):

Cell Lines ◽

Cell Clone ◽

293T Cell ◽

Scaffold Protein ◽

Response To Treatment ◽

Cell Type ◽

Specific Expression ◽

Sequence Element ◽

Cell Type Specific Expression ◽

Cell Type Specific

ABSTRACTThe use of alternative promoters for the cell type-specific expression of a given mRNA/protein is a common cell strategy. NEMO is a scaffold protein required for canonical NF-κB signaling. Transcription of the NEMO gene is primarily controlled by two promoters: one (promoter B) drives NEMO transcription in most cell types and the second (promoter A) is largely responsible for NEMO transcription in liver cells. Herein, we have used a CRISPR/Cas9-based approach to disrupt a core sequence element of promoter B, and this genetic editing essentially eliminates expression of NEMO mRNA and protein in 293T human kidney cells. By cell subcloning, we have isolated targeted 293T cell lines that express no detectable NEMO protein, have defined genomic alterations at promoter B, and do not support canonical NF-κB signaling in response to treatment with tumor necrosis factor (TNF). Nevertheless, non-canonical NF-κB signaling is intact in these NEMO-deficient cells. Expression of ectopic NEMO in the edited cells restores downstream NF-κB signaling in response to TNF. Targeting of the promoter B element does not substantially reduce NEMO expression (from promoter A) in the human SNU-423 liver cancer cell line. We have also used homology directed repair (HDR) to fix the promoter B element in a 293T cell clone. Overall, we have created a strategy for selectively eliminating cell type-specific expression from an alternative promoter and have generated 293T cell lines with a functional knockout of NEMO. The implications of these findings for further studies and for therapeutic approaches to target canonical NF-κB signaling are discussed.

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