Oncostatin M stimulates transcription of the human alpha 2(I) collagen gene via the Sp1/Sp3-binding site
Oncostatin M stimulates transcription of the human alpha 2(I) collagen gene via the Sp1/Sp3-binding site
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DOI：
10.1074/jbc.272.39.24666
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发表时间：
1997-09-26
影响因子：
4.8
通讯作者：
Trojanowska, M
中科院分区：
文献类型：
--
作者：
Ihn, H;LeRoy, EC;Trojanowska, M
抑瘤素M（Oncostatin M，OSM）是造血细胞因子家族的一员，与骨过度生长和纤维化过程有关。作为纤维化分子机制研究的一部分，我们研究了人成纤维细胞中OSM对α 2（I）胶原基因的转录调控，通过α（I）胶原启动子中碱基对（bp）-148和-108之间的缺失分析定位OSM响应元件，α 2的进一步功能分析（I）含有各种取代突变的胶原蛋白启动子揭示了该启动子的基础活性和OSM刺激都是由一个TCCTCC基序位于bp -128和-123之间。电泳迁移率变动分析表明，TCCTCC基序构成了转录因子Sp1和Sp3的一个新的结合位点。在体外凝胶位移结合试验中未观察到OSM刺激和OSM刺激的成纤维细胞之间的差异，然而，使用体内足迹分析在OSM刺激后在TCC重复序列周围的启动子区域中检测到细微的构象变化。总之，本研究表征了介导人α 2（I）胶原启动子的基础活性和OSM刺激的双功能反应元件。
Oncostatin M (OSM), a member of the hematopoietic cytokine family, has been implicated in excessive bone growth and in the process of fibrosis, As part of an ongoing study of the molecular mechanisms of fibrosis, we have investigated the transcriptional regulation of the alpha 2(I) collagen gene by OSM in human fibroblasts, An OSM response element was mapped by deletional analysis between base pairs (bp) -148 and -108 in the alpha(I) collagen promoter, Further functional analysis of the alpha 2(I) collagen promoter containing various substitution mutations revealed that both the basal activity and OSM stimulation of this promoter are mediated by a TCCTCC motif located between bp -128 and -123. Futhermore, three copies of the 12-bp synthetic alpha 2(I) collagen promoter fragment containing the ''TCC'' motif conferred OSM inducibility to the otherwise unresponsive thymidine kinase promoter, Electrophoretic mobility shift assays demonstrated that the TCCTCC motif constitutes a novel binding site far the transcription factors Spl and Sp3. No differences have been observed in in vitro gel shift binding assays between unstimulated and OSM-stimulated fibroblasts, However, subtle conformational changes were detected in the region of the promoter surrounding TCC repeats after OSM stimulation using in vivo footprint analysis. In conclusion, this study characterized a dual-function response element that mediates the basal activity and OSM stimulation of the human alpha 2(I) collagen promoter.