Work

Tumour necrosis factor-α regulates expression of the CCAAT-enhancer-binding proteins (C/EBPs) α and β and determines the occupation of the C/EBP site in the promoter of the insulin-responsive glucose-transporter gene in 3T3-L1 adipocytes

Year: 1999

Type: article

Abstract: We have demonstrated previously that treatment of 3T3-L1 adipocytes with tumour necrosis factor-alpha (TNF) results in a rapid (4 h) and significant (75-80%) reduction in the rate of transcription of the GLUT4 gene. Control of GLUT4 gene transcription has been suggested at least in part to reside with the CCAAT-enhancer-binding protein (C/EBP) family (alpha, beta and delta isoforms) of transcription factors. Using electrophoretic mobility shift assays, we have examined the ability of TNF to alter the occupation of the C/EBP site in the GLUT4 promoter. The data suggest that in fully differentiated adipocytes the C/EBP site is a ligand for predominantly alpha/alpha homodimers; however, after exposure to TNF, a shift in occupancy of the site occurs and the ligands become alpha/beta heterodimers and beta/beta homodimers. Partner selection in dimer formation appears to be controlled by selective translocation of the beta-isoform from the cytosol to the nucleus after exposure of the cells to TNF.

Source: Biochemical Journal

DOI: 10.1042/0264-6021:3380737

Authors: Renu JAIN, Shailaja POLICE, Kelle PHELPS, Phillip H. PEKALA

Institution: East Carolina University

Language: English

Topic: Adipokines, Inflammation, and Metabolic Diseases

Subfield: Epidemiology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: bronze

Funders: National Institutes of Health, National Institute of General Medical Sciences