Inhibition of E-selectin gene transcription through a cAMP-dependent protein kinase pathway.
Cytokines induce the expression of E-selectin, VCAM-1, and ICAM-1 on human umbilical vein endothelial cells (HUVECs). We show that expression of these surface proteins is differently affected by cAMP. Increased cAMP levels decrease E-selectin and VCAM-1 but increase ICAM-1 expression. We demonstrate by mRNA half-life analysis and nuclear run-on assays that the cAMP repression of E-selectin occurs at the transcription level. This effect is abolished by protein kinase A inhibition, suggesting that repression is mediated by protein kinase A-driven phosphorylation. We found that a minimal E-selectin promoter sequence necessary to confer cytokine inducibility is also sufficient to mimic the cAMP effect in transfected HUVECs. Previously we characterized two regions (NF-kappa B and NF-ELAM1) of the minimal promoter that bind transcription factors necessary for E-selectin induction, Increased cAMP did not alter the binding of the complexes formed on either the NF-kappa B or NF-ELAM1 site. In contrast, in interleukin-1-treated HUVECs transactivity due to an NF-kappa B site is reduced by elevated cAMP. Increased cAMP in HUVECs appears to induce a protein kinase activity that reduces the cytokine signal for E-selectin and VCAM-1 expression. The reduction in signal may occur through an inhibitory phosphorylation of one or more of the factors responsible for regulating E-selectin expression.
Ghersa
P
P
Glaxo Institute for Molecular Biology, Geneva, Switzerland.
Hooft van Huijsduijnen
R
R
Whelan
J
J
Cambet
Y
Y
Pescini
R
R
DeLamarter
J F
JF
D001483:Base Sequence; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000235:genetics* / Q000378:metabolism; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D019040:E-Selectin; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D009838:Oligodeoxyribonucleotides; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic; D019010:Vascular Cell Adhesion Molecule-1
D015815:Cell Adhesion Molecules; D019040:E-Selectin; D009687:Nuclear Proteins; D009838:Oligodeoxyribonucleotides; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D005576:Colforsin; D004247:DNA; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D013755:Tetradecanoylphorbol Acetate