A novel cis-element that enhances connective tissue growth factor gene expression in chondrocytic cells
A novel cis-element that enhances connective tissue growth factor gene expression in chondrocytic cells
复制标题
DOI：
10.1016/s0006-291x(02)00700-3
复制
发表时间：
2002-07-12
影响因子：
3.1
通讯作者：
Takigawa, M
中科院分区：
文献类型：
--
作者：
Eguchi, T;Kubota, S;Takigawa, M
为了阐明结缔组织生长因子（CTGF）基因表达的软骨细胞特异性调节机制，我们分析了CTGF启动子的功能和DNA-蛋白质相互作用。比较HCS-2/8软骨细胞和成纤维细胞中CTGF启动子缺失突变体的荧光素酶测定显示，启动子中的110 bp区域对于HCS-2/8特异性转录增强至关重要。随后的竞争性凝胶迁移实验显示，HCS-2/8细胞核中的转录因子与相应区域的60 bp部分结合。CTGF启动子与突变的TGF-β反应元件（TbRE）的相对荧光素酶活性比一个完整的启动子低16.9%。另一方面，在TbRE上游30 bp处具有4 bp点突变的CTGF启动子的相对荧光素酶活性比完整的CTGF启动子低47.7%。HCS-2/8核因子与4 bp以上序列的结合活性明显高于其他类型细胞的核提取物。因此，我们将序列命名为“TRENDIC”，这是一种在软骨细胞中占主导地位的转录增强子，代表软骨细胞特异性CTGF基因表达的新型增强子。(C)2002 Elsevier Science（美国）。All rights reserved.
To clarify the chondrocyte-specific regulatory mechanism of connective tissue growth factor (ctgf) gene expression, we analyzed the functionality and DNA-protein interaction of the CTGF promoter. Comparative luciferase assay of the CTGF promoter deletion mutants among HCS-2/8 chondrocytic cells and fibroblastic cells revealed that a 110-bp region in the promoter was crucial for the HCS-2/8-specific transcriptional enhancement. Subsequent competitive gel shift assay revealed that transcription factors in HCS-2/8 nuclei bound to a 60-bp portion in the corresponding region. Relative luciferase activity from a CTGF promoter with mutant TGF-beta response element (TbRE) was 16.9% lower than that from an intact promoter. On the other hand, relative luciferase activity from a CTGF promoter with 4 bp point mutations at 30 bp upstream of the TbRE was 47.7% lower than that from the intact one. The binding activity of HCS-2/8 nuclear factor(s) to the sequence over the 4-bp was remarkably higher than that of any nuclear extract from other types of cells. Therefore, we entitled the sequence 'TRENDIC', a transcription enhancer dominant in chondrocytes, which stands for a novel enhancer for chondrocyte-specific CTGF gene expression. (C) 2002 Elsevier Science (USA). All rights reserved.