Distamycin prolongs E-selectin expression by interacting with a specific NF-kappaB-HMG-I(Y) binding site in the promoter.
The E-selectin cell adhesion protein plays a critical role in mediating adherence of leukocytes to endothelium at sites of inflammation. Cytokine-induced E-selectin expression on the surface of endothelial cells is transient; mRNA expression peaks at 3-4 h after induction and returns to basal levels within 24 h. The mechanism for this transcriptional down-modulation is not known. Promoter binding factors responsible for induced gene expression include NF-kappaB, which binds at three sites within the E-selectin promoter, and HMG-I(Y), which binds to the A/T-rich core found at the centre of these binding sites. Distamycin is an antibiotic that also binds A/T-rich DNA and inhibits HMG-I(Y) DNA binding. To study the role of HMG-I(Y) in E-selectin expression, we have examined the effect of distamycin on the cytokine-induced E-selectin expression cycle. We found that distamycin prolonged E-selectin expression, both by sustaining mRNA transcription and by extending the transcript's half-life. The distamycin effect on transcription was mediated through one of the three NF-kappaB-HMG-I(Y) binding sites (NF-kappaBII) within the promoter. This suggests that the NF-kappaB-HMG-I(Y) complex interacting at the NF-kappaBII site plays a role not only in cytokine induction of E-selectin expression, but also in its down-modulation.
Ghersa
P
P
Geneva Biomedical Research Institute, 14, Chemin des Aulx, Case Postale 674, 1228 Plan-les-Ouates, Geneva, Switzerland. pfg8091@ggr.co.uk
Whelan
J
J
Cambet
Y
Y
DeLamarter
J F
JF
Hooft van Huijsduijnen
R
R
D001665:Binding Sites / Q000235:genetics; D015152:Blotting, Northern; D002478:Cells, Cultured; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004214:Distamycins / Q000494:pharmacology*; D015536:Down-Regulation / Q000502:physiology; D019040:E-Selectin / Q000235:genetics / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000235:genetics*; D017930:Genes, Reporter / Q000235:genetics; D025741:HMGA1a Protein; D006609:High Mobility Group Proteins / Q000378:metabolism*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D016328:NF-kappa B / Q000378:metabolism*; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D004268:DNA-Binding Proteins; D004214:Distamycins; D019040:E-Selectin; D006609:High Mobility Group Proteins; D007375:Interleukin-1; D016328:NF-kappa B; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D025741:HMGA1a Protein; C030000:stallimycin