title: Identification of nuclear factor-κB sites in the Slc2a4 gene promoter.
abstract: Glucose transporter GLUT4 protein, codified by Slc2a4 gene plays a key role in glycemic homeostasis. Insulin resistance, as in obesity, has been associated to inflammatory state, in which decreased GLUT4 is a feature. Inflammatory NF-κB transcriptional factor has been proposed as a repressor of Slc2a4; although, the binding site(s) in Slc2a4 promoter and the direct repressor effect have never been reported yet. A motif-based sequence analysis of mouse Slc2a4 promoter revealed two putative κB sites located inside -83/-62 and -134/-113 bp. Eletrophoretic mobility assay showed that p50 and p65 NF-κB subunits bind to both putative κB sites. Chromatin immunoprecipitation assay using genomic DNA from adipocytes confirmed p50- and p65-binding to Slc2a4 promoter. Moreover, transfection experiments revealed that NF-κB binds to the -134/-113bp region of the mouse Slc2a4 gene promoter, inhibiting the Slc2a4 gene transcription. The current findings demonstrate the existence of two κB sites in Slc2a4 gene promote, and that NF-κB has a direct repressor effect upon the Slc2a4 gene, providing an important link between insulin resistance and inflammation.
authors: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil. danifuruya@yahoo.com
authors: D T
authors: DT
authors: Furuya
authors: E A
authors: EA
authors: Neri
authors: A C
authors: AC
authors: Poletto
authors: G F
authors: GF
authors: Anhê
authors: H S
authors: HS
authors: Freitas
authors: R S
authors: RS
authors: Campello
authors: N A
authors: NA
authors: Rebouças
authors: U F
authors: UF
authors: Machado
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins / Q000378:metabolism; D051275:Glucose Transporter Type 4 / Q000235:genetics* / Q000378:metabolism; D007249:Inflammation / Q000235:genetics; D007333:Insulin Resistance / Q000235:genetics; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D052002:NF-kappa B p50 Subunit / Q000378:metabolism*; D009765:Obesity / Q000235:genetics; D011401:Promoter Regions, Genetic; D051381:Rats; D017422:Sequence Analysis, DNA; D051996:Transcription Factor RelA / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D004268:DNA-Binding Proteins; D051275:Glucose Transporter Type 4; D016328:NF-kappa B; D052002:NF-kappa B p50 Subunit; C498144:Rela protein, mouse; C495693:Slc2a4 protein, mouse; D051996:Transcription Factor RelA