Umetani M, Mataki C, Minegishi N, Yamamoto M, Hamakubo T, Kodama T
Department of Molecular Biology and Medicine, Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.
Arterioscler Thromb Vasc Biol. 2001 Jun;21(6):917-22. doi: 10.1161/01.atv.21.6.917.
Endothelial vascular cell adhesion molecule-1 (VCAM-1) is expressed in response to cytokine stimulation and plays a critical role in inflammatory reactions. Previously, we developed a novel VCAM-1 inhibitor that acts through a mechanism independent of nuclear factor-kappaB activity. It suppresses the binding activity of GATA proteins in cytokine-stimulated endothelial cells, which may be related to the anti-VCAM-1 induction effect of this drug. In this study, we investigated the role of GATA proteins in the induction of VCAM-1 by tumor necrosis factor-alpha (TNF-alpha) in human endothelial cells. The mRNA expression of GATA-6 was increased, whereas GATA-3 mRNA was decreased by TNF-alpha stimulation. Electrophoretic mobility shift assay showed that TNF-alpha stimulation increased the DNA binding of GATA-6 but decreased that of GATA-3. Experiments using protein overexpression or antisense oligonucleotides revealed that GATA-6 potently acts as a positive regulator of VCAM-1 gene transcription. In contrast, overexpression of GATA-3 was able to suppress TNF-alpha-induced VCAM-1 expression. Our results provide evidence of the importance of GATA proteins in the induction of VCAM-1 by TNF-alpha in vascular endothelial cells. The switch from GATA-3 to GATA-6 is taken to be an important transcriptional control event in TNF-alpha induction of VCAM-1.
内皮血管细胞黏附分子-1(VCAM-1)在细胞因子刺激下表达,并在炎症反应中起关键作用。此前,我们开发了一种新型的VCAM-1抑制剂,其作用机制独立于核因子-κB活性。它抑制细胞因子刺激的内皮细胞中GATA蛋白的结合活性,这可能与该药物的抗VCAM-1诱导作用有关。在本研究中,我们研究了GATA蛋白在肿瘤坏死因子-α(TNF-α)诱导人内皮细胞VCAM-1中的作用。TNF-α刺激后,GATA-6的mRNA表达增加,而GATA-3的mRNA表达减少。电泳迁移率变动分析表明,TNF-α刺激增加了GATA-6与DNA的结合,但减少了GATA-3与DNA的结合。使用蛋白质过表达或反义寡核苷酸的实验表明,GATA-6有力地作为VCAM-1基因转录的正调节因子。相反,GATA-3的过表达能够抑制TNF-α诱导的VCAM-1表达。我们的结果提供了证据,证明GATA蛋白在TNF-α诱导血管内皮细胞VCAM-1中的重要性。从GATA-3到GATA-6的转变被认为是TNF-α诱导VCAM-1过程中的一个重要转录控制事件。