Gene expression profiling leads to identification of GLI1-binding elements in target genes and a role for multiple downstream pathways in GLI1-induced cell transformation
Gene expression profiling leads to identification of GLI1-binding elements in target genes and a role for multiple downstream pathways in GLI1-induced cell transformation
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DOI：
10.1074/jbc.m105708200
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发表时间：
2002-02-15
影响因子：
4.8
通讯作者：
Iannaccone, P
中科院分区：
文献类型：
--
作者：
Yoon, JW;Kita, Y;Iannaccone, P
锌指转录因子GLI 1在发育过程中介导Sonic hedgehog信号传导，在几种人类癌症中表达，包括基底细胞癌、成神经管细胞瘤和肉瘤。我们确定了147个基因，其表达水平显着改变的RNA从细胞表现出转化表型与稳定的GLI 1表达或稳定的Ha-ras表达。比较GLI 1和Ha-ras表达细胞的表达谱，建立了一组GLI 1诱导细胞转化的独特基因。GLI 1稳定表达改变了30个基因，Ha-ras稳定表达改变了124个基因。7个基因在GLI 1和Ha-ras表达细胞中的表达水平发生了改变。其表达被GLI 1改变的基因包括细胞周期基因、细胞粘附基因、信号转导基因和调节细胞凋亡的基因。在细胞周期蛋白D2、IGFBP-6、骨桥蛋白和斑珠蛋白的5'区鉴定了GLI 1共有DNA结合序列，表明这些基因代表直接下游靶点。凝胶位移分析证实了GLI 1蛋白结合这些序列的能力。与未扩增的人横纹肌肉瘤细胞相比，GLI 1扩增的细胞周期蛋白D2上调，斑珠蛋白下调。本研究中鉴定的许多具有已知功能的GLI 1靶点可增加细胞增殖，表明GLI 1诱导的细胞转化通过多个下游途径发生。
The zinc finger transcription factor GLI1, which mediates Sonic hedgehog signaling during development, is expressed in several human cancers, including basal cell carcinoma, medulloblastoma, and sarcomas. We identified 147 genes whose levels of expression were significantly altered in RNA obtained from cells demonstrating a transformed phenotype with stable GLI1 expression or stable Ha-ras expression. Comparison of expression profiles from GLI1- and Ha-ras-expressing cells established a set of genes unique to GLI1-induced cell transformation. Thirty genes were altered by stable GLI1 expression, and 124 genes were changed by stable Ha-ras expression. Seven genes had altered expression levels in both GLI1- and Ha-ras-expressing cells. Genes whose expression was altered by GLI1 included cell cycle genes, cell adhesion genes, signal transduction genes, and genes regulating apoptosis. GLI1 consensus DNA-binding sequences were identified in the 5' regions of cyclin D2, IGFBP-6, osteopontin, and plakoglobin, suggesting that these genes represent immediate downstream targets. Gel shift analysis confirmed the ability of the GLI1 protein to bind these sequences. Up-regulation of cyclin D2 and down-regulation of plakoglobin were demonstrated in GLI1-amplified compared with non-amplified hum an rhabdomyosarcoma cells. Many of the GLI1 targets with known function identified in this study increase cell proliferation, indicating that GLI1-induced cell transformation occurs through multiple downstream pathways.