Sims S H, Cha Y, Romine M F, Gao P Q, Gottlieb K, Deisseroth A B
Department of Hematology, University of Texas M. D. Anderson Cancer Center, Houston 77030.
Mol Cell Biol. 1993 Jan;13(1):690-702. doi: 10.1128/mcb.13.1.690-702.1993.
We have cloned and functionally characterized the human interferon regulatory factor 1 (IRF-1) gene promoter. The promoter contains a CpG island, with several GC boxes, a CAAT box, but no TATA box. IRF-1 mRNA is strongly induced by gamma interferon (IFN-gamma) but more weakly and transiently by IFN-alpha. There are several putative kappa B motifs and numerous AA(G/A)G(G/T)A and GAAANN motifs throughout the promoter. The IRF-1 promoter is not autoregulated by the IRF-1 gene product. IFN inducibility of the promoter was studied with 5' deletion mutants linked to a heterologous reporter gene. Gel mobility shift assays were used to show IFN-inducible factor binding to the IRF-1 promoter. These studies showed that IFN inducibility is conferred by a novel imperfect inverted-repeat arrangement of two GAAANN motifs within a domain, 130 nucleotides upstream of transcription initiation. This inverted repeat binds a factor upon induction with IFN and can confer IFN inducibility on a heterologous promoter. Conversely, point mutations of the inverted repeat are not IFN inducible when linked to the same heterologous promoter.
我们已经克隆了人干扰素调节因子1（IRF-1）基因启动子并对其进行了功能表征。该启动子包含一个CpG岛，有几个GC盒、一个CAAT盒，但没有TATA盒。IRF-1 mRNA受到γ干扰素（IFN-γ）的强烈诱导，但受到IFN-α的诱导较弱且短暂。在整个启动子中有几个假定的κB基序以及众多AA（G/A）G（G/T）A和GAAANN基序。IRF-1启动子不受IRF-1基因产物的自动调节。用与异源报告基因相连的5'缺失突变体研究了该启动子的IFN诱导性。凝胶迁移率变动分析用于显示IFN诱导因子与IRF-1启动子的结合。这些研究表明，IFN诱导性是由转录起始上游130个核苷酸处一个结构域内两个GAAANN基序的新型不完全反向重复排列赋予的。这种反向重复在受到IFN诱导时会结合一个因子，并能将IFN诱导性赋予异源启动子。相反，当与相同的异源启动子相连时，反向重复的点突变不具有IFN诱导性。
