title: Tumor Necrosis Factor α Induces the Expression of the Endothelial Cell-Specific Receptor Roundabout4 through the Nuclear Factor-κB Pathway.
abstract: Roundabout4 (Robo4) is an endothelial cell-specific receptor that regulates vascular stability. Recently, Robo4 has been shown to regulate vascular permeability in inflammation. However, the mechanisms regulating the Robo4 gene in the context of inflammation are poorly understood. In this study, we found that intravenous injection of tumor necrosis factor (TNF) α increased Robo4 expression in mouse organs. In vitro analyses showed that TNFα increased Robo4 expression in human primary endothelial cells, but not in cells pretreated with a nuclear factor (NF)-κB inhibitor. Reporter assays using wild-type and mutant Robo4 promoters indicated that TNFα activated the Robo4 promoter and that both the -2753 and -2220 NF-κB motifs were essential for this activation. Electrophoretic mobility shift assays demonstrated that the NF-κB p65-p50 heterodimer bound to these motifs. These findings were further supported by chromatin immunoprecipitation assays in endothelial cells. Taken together, these results indicated that TNFα induced Robo4 expression by facilitating NF-κB p65-p50 heterodimer binding to the -2753 and -2220 motifs in the Robo4 promoter in endothelial cells in the context of inflammation.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University.
authors.forename: Toru
authors.initials: T
authors.lastname: Tanaka
authors.forename: Naoki
authors.initials: N
authors.lastname: Maekawa
authors.forename: Taito
authors.initials: T
authors.lastname: Kashio
authors.forename: Kohei
authors.initials: K
authors.lastname: Izawa
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Ishiba
authors.forename: Keisuke
authors.initials: K
authors.lastname: Shirakura
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishimoto
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Hino
authors.forename: William C
authors.initials: WC
authors.lastname: Aird
authors.forename: Takefumi
authors.initials: T
authors.lastname: Doi
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Okada
mesh_terms: D000818:Animals; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism*; D015870:Gene Expression; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000187:drug effects* / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic / Q000096:biosynthesis*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage*
chemical_list: D016328:NF-kappa B; D009419:Nerve Tissue Proteins; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; C540792:Robo4 protein, mouse; D014409:Tumor Necrosis Factor-alpha