Eklund E A, Luo W, Skalnik D G
Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis 46202, USA.
J Immunol. 1996 Sep 15;157(6):2418-29.
The cytochrome b558 heavy chain (gp9l-phox) is expressed in terminally differentiated myelomonocytic cells. Three cis-elements located between -450 and -100 bp of the gp91-phox promoter are required for IFN-gamma induced transcription. Mutations that disrupt individual cis-elements incrementally decrease gp9l-phox promoter activity, and one of the two proximal elements must be present for an IFN-gamma response. The DNA-binding activities that interact with each of the cis-elements exhibit similar gel mobility and binding site specificity, although a consensus binding site common to the three elements is not apparent. An increased level of each DNA/protein complex is observed in myeloid cells following treatment with PMA, retinoic acid/dimethylformamide, or IFN-gamma, but not in similarly treated HeLa cells. The myeloid-specific increase in the intensity of each complex is delayed 12 to 24 h following IFN-gamma treatment, and the complexes are not immunoreactive with antisera directed against IFN-responsive factors such as IRF-1, IRF-2, IFN consensus sequence binding protein, Stat1, and IFN-stimulated gene factor-3 gamma, although IRF-2 is additionally detected as binding to the middle cis-element. These results reveal cis-elements and a DNA-binding factor(s) that participate in a common pathway in response to various stimuli that induce gp9l-phox transcription.
细胞色素b558重链（gp91 - phox）在终末分化的骨髓单核细胞中表达。gp91 - phox启动子-450至-100 bp之间的三个顺式元件是γ干扰素诱导转录所必需的。破坏单个顺式元件的突变会逐渐降低gp91 - phox启动子活性，并且两个近端元件中的一个必须存在才能产生γ干扰素反应。与每个顺式元件相互作用的DNA结合活性表现出相似的凝胶迁移率和结合位点特异性，尽管这三个元件共有的一致结合位点并不明显。在用佛波酯、视黄酸/二甲基甲酰胺或γ干扰素处理后的骨髓细胞中，观察到每个DNA/蛋白质复合物的水平增加，但在同样处理的HeLa细胞中未观察到。γ干扰素处理后，每个复合物强度的骨髓特异性增加延迟12至24小时，并且这些复合物与针对干扰素反应因子（如IRF - 1、IRF - 2、干扰素共有序列结合蛋白、Stat1和干扰素刺激基因因子-3γ）的抗血清无免疫反应，尽管另外检测到IRF - 2与中间顺式元件结合。这些结果揭示了参与响应诱导gp91 - phox转录的各种刺激的共同途径的顺式元件和一种或多种DNA结合因子。
