The transcription factors HIF-1 and HNF-4 and the coactivator p300 are involved in insulin-regulated glucokinase gene expression via the phosphatidylinositol 3-kinase/protein kinase B pathway

被引:89
作者
Roth, U
Curth, K
Unterman, TG
Kietzmann, T
机构
[1] Univ Gottingen, Inst Biochem & Mol Zellbiol, D-37073 Gottingen, Germany
[2] Univ Illinois, Dept Med, Chicago, IL 60612 USA
[3] Univ Illinois, Dept Physiol & Biophys, Chicago, IL 60612 USA
[4] Vet Affair Chicago Healthcare Syst, Chicago, IL 60612 USA
关键词
D O I
10.1074/jbc.M308391200
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Glucokinase plays a key role in the regulation of glucose utilization in liver and its expression is strongly enhanced by insulin and modulated by venous pO(2). In primary rat hepatocytes, pO(2) modulated insulin-dependent glucokinase (GK) gene expression was abolished by wortmannin an inhibitor of phosphatidylinositol 3-kinase (PI3K). Transfection of vectors encoding the p110 catalytic subunit of PI3K or constitutively active proteinkinase B (PKB) stimulated GK mRNA and protein expression. The transfection of GK promoter constructs together with expression vectors for p110 or constitutively active PKB revealed that the GK promoter region -87/-80 mediates the response to PI3K/PKB. Transfection experiments and gel shift assays show that this element is able to bind hypoxia-inducible factor-1 (HIF-1) in a hypoxia- and PKB-dependent manner. The ability of HIF-1alpha to activate the GK promoter was enhanced by hepatocyte nuclear factor-4alpha (HNF-4alpha), acting via the sequence -52/-39, and by the coactivator p300. Stimulation of the GK promoter by insulin was dependent on the intact -87/-80 region and maximal stimulation was achieved when HIF-1alpha, HNF-4, and p300 were co-transfected with the -1430 GK promoter Luc construct in primary hepatocytes. Maximal stimulation of GK promoter activity by insulin was inhibited when a p300 vector was used containing a mutation within a PKB phosphorylation site. Thus, a regulatory transcriptional complex consisting of HIF-1, HNF-4, and p300 appears to be involved in insulin-dependent GK gene activation.
引用
收藏
页码:2623 / 2631
页数:9
相关论文
共 69 条
[1]   Characterization of a 3-phosphoinositide-dependent protein kinase which phosphorylates and activates protein kinase B alpha [J].
Alessi, DR ;
James, SR ;
Downes, CP ;
Holmes, AB ;
Gaffney, PRJ ;
Reese, CB ;
Cohen, P .
CURRENT BIOLOGY, 1997, 7 (04) :261-269
[2]   An essential role for p300/CBP in the cellular response to hypoxia [J].
Arany, Z ;
Huang, LE ;
Eckner, R ;
Bhattacharya, S ;
Jiang, C ;
Goldberg, MA ;
Bunn, HF ;
Livingston, DM .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1996, 93 (23) :12969-12973
[3]   Regulation of GLUT1 gene transcription by the serine threonine kinase Akt1 [J].
Barthel, A ;
Okino, ST ;
Liao, JF ;
Nakatani, K ;
Li, JP ;
Whitlock, JP ;
Roth, RA .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1999, 274 (29) :20281-20286
[4]   The SREBP pathway: Regulation of cholesterol metabolism by proteolysis of a membrane-bound transcription factor [J].
Brown, MS ;
Goldstein, JL .
CELL, 1997, 89 (03) :331-340
[5]   Oxygen sensing and molecular adaptation to hypoxia [J].
Bunn, HF ;
Poyton, RO .
PHYSIOLOGICAL REVIEWS, 1996, 76 (03) :839-885
[6]   Structural basis for Hif-1α/CBP recognition in the cellular hypoxic response [J].
Dames, SA ;
Martinez-Yamout, M ;
De Guzman, RN ;
Dyson, HJ ;
Wright, PE .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2002, 99 (08) :5271-5276
[7]   Regulation of transcription by hypoxia requires a multiprotein complex that includes hypoxia-inducible factor 1, an adjacent transcription factor, and p300/CREB binding protein [J].
Ebert, BL ;
Bunn, HF .
MOLECULAR AND CELLULAR BIOLOGY, 1998, 18 (07) :4089-4096
[8]   A novel bHLH-PAS factor with close sequence similarity to hypoxia-inducible factor 1 alpha regulates the VEGF expression and is potentially involved in lung and vascular development [J].
Ema, M ;
Taya, S ;
Yokotani, N ;
Sogawa, K ;
Matsuda, Y ;
FujiiKuriyama, Y .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1997, 94 (09) :4273-4278
[9]  
Feldser D, 1999, CANCER RES, V59, P3915
[10]   HRF, a putative basic helix-loop-helix-PAS-domain transcription factor is closely related to hypoxia-inducible factor-1 alpha and developmentally expressed in blood vessels [J].
Flamme, I ;
Frohlich, T ;
vonReutern, M ;
Kappel, A ;
Damert, A ;
Risau, W .
MECHANISMS OF DEVELOPMENT, 1997, 63 (01) :51-60