• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Molecular and Cellular Biology >The von Hippel-Lindau tumor suppressor gene product interacts with Sp1 to repress vascular endothelial growth factor promoter activity.
【24h】

The von Hippel-Lindau tumor suppressor gene product interacts with Sp1 to repress vascular endothelial growth factor promoter activity.

机译：von Hippel-Lindau抑癌基因产物与Sp1相互作用，以抑制血管内皮生长因子启动子的活性。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The von Hippel-Lindau tumor suppressor gene (VHL) has a critical role in the pathogenesis of clear-cell renal cell carcinoma (RCC), as VHL mutations have been found in both von Hippel-Lindau disease-associated and sporadic RCCs. Recent studies suggest that vascular endothelial growth factor (VEGF) mRNA is upregulated in RCC- and von Hippel-Lindau disease-associated tumors. We have therefore assessed the effect of the VHL gene product on VEGF expression. VEGF promoter-luciferase constructs were transiently cotransfected with a wild-type VHL (wt-VHL) vector in several cell lines, including 293 embryonic kidney and RCC cell lines. wt-VHL protein inhibited VEGF promoter activity in a dose-dependent manner up to 5- to 10-fold. Deletion analysis defined a 144-bp region of the VEGF promoter necessary for VHL repression. This VHL-responsive element is GC rich and specifically binds the transcription factor Sp1 in crude nuclear extracts. In Drosophila cells, cotransfected VHL represses Sp1-mediated activation but not basal activity of the VEGF promoter. We next demonstrated in coimmunoprecipitates that VHL and Sp1 were part of the same complex and, by using a glutathione-S-transferase-VHL fusion protein and purified Sp1, that VHL and Sp1 directly interact. Furthermore, endogenous VEGF mRNA levels were suppressed in permanent RCC cell lines expressing wt-VHL, and nuclear run-on studies indicated that VHL regulation of VEGF occurs at least partly at the transcriptional level. These observations support a new mechanism for VHL-mediated transcriptional repression via a direct inhibitory action on Sp1 and suggest that loss of Sp1 inhibition may be important in the pathogenesis of von Hippel-Lindau disease and RCC.
机译：von Hippel-Lindau肿瘤抑制基因（VHL）在透明细胞肾细胞癌（RCC）的发病机理中起着关键作用，因为在von Hippel-Lindau疾病相关的散发性RCC中都发现了VHL突变。最近的研究表明，在RCC和von Hippel-Lindau疾病相关的肿瘤中，血管内皮生长因子（VEGF）mRNA上调。因此，我们评估了VHL基因产物对VEGF表达的影响。将VEGF启动子-荧光素酶构建体与野生型VHL（wt-VHL）载体在包括293个胚胎肾和RCC细胞系在内的几种细胞系中瞬时共转染。 wt-VHL蛋白以剂量依赖的方式抑制VEGF启动子活性达5至10倍。缺失分析定义了VHL阻遏所必需的VEGF启动子的144bp区域。此VHL响应元件富含GC，可特异性结合粗核提取物中的转录因子Sp1。在果蝇细胞中，共转染的VHL抑制Sp1介导的激活，但不抑制VEGF启动子的基础活性。接下来，我们在共沉淀物中证明VHL和Sp1是同一复合物的一部分，并且通过使用谷胱甘肽S-转移酶-VHL融合蛋白和纯化的Sp1，VHL和Sp1直接相互作用。此外，内源性VEGF mRNA水平在表达wt-VHL的永久性RCC细胞系中受到抑制，核实验研究表明，VEGF的VHL调节至少部分在转录水平上发生。这些观察结果通过对Sp1的直接抑制作用支持了VHL介导的转录抑制的新机制，并表明Sp1抑制作用的丧失可能在von Hippel-Lindau病和RCC的发病机理中很重要。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号