Department of Nephrology and Hypertension, University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany.
J Mol Med (Berl). 2010 Jun;88(6):623-31. doi: 10.1007/s00109-010-0608-3. Epub 2010 Mar 24.
The functional role of the LIM-domain protein Hic-5 was investigated in microvascular endothelial cells using a siRNA approach. Knock down of Hic-5 reduced endothelial cell spreading and impaired structural organization of the cells on basement membrane extracts. Furthermore, Hic-5 was involved in the regulation of the multifunctional protein connective tissue growth factor (CTGF, CCN2). Upon Hic-5 down-regulation, induction of CTGF by lysophosphatidic acid or colchicine was reduced. Inhibition of CTGF expression was even more pronounced in cells treated with transforming growth factor beta and inhibitors of histone deacetylases. Treatment of endothelial cells with Hic-5 siRNA reduced CTGF promoter activity. Mutation analyses of the promoter revealed transcription factors binding to the basic control element as part of the proposed Hic-5-modulated transcription complex. Further analyses showed down-regulation of Hic-5 protein upon overnight treatment with inhibitors of histone deacetylases. These data suggest that the reduced expression of Hic-5 may contribute to the anti-angiogenic effects of histone deacetylase inhibitors.
使用 siRNA 方法研究了 LIM 结构域蛋白 Hic-5 在微血管内皮细胞中的功能作用。Hic-5 的敲低降低了内皮细胞的铺展，并损害了细胞在基底膜提取物上的结构组织。此外，Hic-5 参与了多功能蛋白结缔组织生长因子（CTGF，CCN2）的调节。在 Hic-5 下调后，由溶血磷脂酸或秋水仙碱诱导的 CTGF 减少。在用转化生长因子-β和组蛋白去乙酰化酶抑制剂处理的细胞中，CTGF 表达的抑制更为明显。用 Hic-5 siRNA 处理内皮细胞可降低 CTGF 启动子活性。启动子的突变分析显示，转录因子结合到基本调控元件上，作为所提出的 Hic-5 调节转录复合物的一部分。进一步的分析表明，过夜用组蛋白去乙酰化酶抑制剂处理会下调 Hic-5 蛋白。这些数据表明，Hic-5 表达的降低可能有助于组蛋白去乙酰化酶抑制剂的抗血管生成作用。
