Transcription Factor NF1 Mediates Repression of the GLUT4 Promoter by Cyclic-AMP

doi:10.1006/bbrc.1999.0959

Biochemical and Biophysical Research Communications

Volume 260, Issue 3, 14 July 1999, Pages 600-604

https://doi.org/10.1006/bbrc.1999.0959 Get rights and content

Abstract

Prolonged treatment of 3T3-L1 adipocytes with 8-Br-cAMP decreases expression of GLUT4, the insulin-responsive glucose transporter. Expression of a promoter-reporter gene construct that contained 785 base pairs of 5′-flanking region of the murine GLUT4 gene was down regulated by 8-Br-cAMP (p < 0.001), whereas expression of constructs that contained 641 or 469 base pairs of 5′-flanking region was not. A reporter gene construct in which bases −706 to −676 were deleted was not repressed by 8-Br-cAMP, thereby identifying a 30 bp region as necessary for repression of the GLUT4 promoter by 8-Br-cAMP. Mutations in this regulatory element that disrupt binding of the transcription factor NF1 abolish the 8-Br-cAMP-induced repression of the gene. Although insulin and cAMP both repress the GLUT4 promoter through this cis-element, they appear to do this through different mechanisms, as treatment with 8-Br-cAMP does not induce the phosphorylation of NF1 that is induced by insulin treatment.

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Regular ArticleTranscription Factor NF1 Mediates Repression of the GLUT4 Promoter by Cyclic-AMP

Abstract

Journal of Biological Chemistry

Biochemical & Biophysical Research Communications

International Journal of Biochemistry

Journal of Biological Chemistry

Journal of Biological Chemistry

Endocrine Reviews

Regular Article
Transcription Factor NF1 Mediates Repression of the GLUT4 Promoter by Cyclic-AMP