Cloning and sequencing of the proximal promoter of the rat iNOS gene: Activation of NF kappa B is not sufficient for transcription of the iNOS gene in rat mesangial cells
Cloning and sequencing of the proximal promoter of the rat iNOS gene: Activation of NF kappa B is not sufficient for transcription of the iNOS gene in rat mesangial cells
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DOI：
10.1016/0014-5793(96)00966-0
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发表时间：
1996-10-07
期刊：
影响因子：
3.5
通讯作者：
Sterzel, RB
中科院分区：
文献类型：
--
作者：
Beck, KF;Sterzel, RB
先前已经表明，诱导型NO合酶（EC 1.14.23）的表达在转录水平上受到控制，并且诱导型NOS转录依赖于NF κ B家族转录因子的激活。TNF-α和IL-1 β协同刺激大鼠肾小球系膜细胞iNOS转录我们最近报道，内皮素-1完全阻断尼古丁诱导的iNOS在转录水平上的表达。为了进一步研究NF κ B B在烟碱诱导的iNOS转录中的分子机制和作用，我们克隆了一个661 bp的大鼠基因组DNA片段，其中包含497 bp的近端iNOS启动子。鉴定了与鼠序列所述相同的NF κ B结合位点，并用于电泳迁移率变化实验。我们发现，在系膜细胞中，NF κ B B的结合被IL-1 β和TNF-α强烈诱导。虽然内皮素-1阻断了精氨酸诱导的iNOS表达，但对NF κ B B的结合模式没有影响。我们从这些数据中得出结论，系膜细胞中iNOS的转录除了激活NF κ B B外还需要额外的信号。
It has previously been shown that expression of the inducible form of NO synthase (EC 1.14.23) is controlled at the transcriptional level and that induction of iNOS transcription is dependent on activation of transcription factors of the NF kappa B family. TNF-alpha and IL-1 beta synergistically stimulate iNOS transcription in rat glomerular mesangial cells. We have recently reported that endothelin-1 completely blocks cytokine-induced iNOS expression at the transcriptional level. To further investigate the molecular mechanisms and the role of NF kappa B in cytokine-elicited iNOS transcription, we cloned a 661 bp genomic rat DNA fragment, which contains 497 bp of the proximal iNOS promoter. An NF kappa B-binding site identical to that described for the murine sequence was identified and used for electrophoretic mobility shift experiments. We found that binding of NF kappa B is strongly induced in mesangial cells by both IL-1 beta and TNF-alpha. While endothelin-1 blocks cytokine-induced iNOS expression, it has no influence on the binding pattern of NF kappa B. We conclude from these data that transcription of iNOS in mesangial cells requires additional signals besides activation of NF kappa B.