Department of Life Science, Dongguk University-Seoul, Seoul, South Korea.
Intervirology. 2011 Feb;54(2):66-77. doi: 10.1159/000318871. Epub 2010 Sep 10.
To determine the participation of the SWI/SNF complex in the transcription and replication of human papillomavirus (HPV) E2 protein.
We checked the interaction between hSNF5 and HPV E2 through glutathione S-transferase (GST) pull-down and coimmunoprecipitation assays. The transcriptional activation of E2 was analyzed by reporter assay and the level of HPV DNA replication was determined by a transient DNA replication assay.
We demonstrated that hSNF5 binds to the HPV E2 protein in vivo and in vitro and activates E2-dependent viral transcription. SWI/SNF components enhanced E2-dependent viral transcription. The ATPase activity of BRG-1/hSNF2 was required for efficient E2-dependent transcriptional activation. Transient DNA replication assays showed that hSNF5 and BRG-1 enhance HPV-18 DNA replication in vivo. A dominant negative hSNF5 and a BRG-1 ATPase mutant each repressed E2-dependent viral transcription and E2-driven HPV DNA replication in vivo. The fact that the transcriptional activation function of HPV-18 E2 was defective in the SNF5 knockout strains of the yeast Saccharomyces cerevisiae implies that the SWI/SNF complex is required for the transcriptional activation function of E2.
These results suggest that the SWI/SNF complex is involved in HPV E2-driven transcription and DNA replication via interaction with E2.
确定 SWI/SNF 复合物在人乳头瘤病毒（HPV）E2 蛋白转录和复制中的参与情况。
我们通过谷胱甘肽 S-转移酶（GST）下拉和共免疫沉淀实验检查了 hSNF5 与 HPV E2 之间的相互作用。通过报告基因实验分析 E2 的转录激活，通过瞬时 DNA 复制实验确定 HPV DNA 复制水平。
我们证明 hSNF5 在体内和体外与 HPV E2 蛋白结合，并激活 E2 依赖性病毒转录。SWI/SNF 成分增强了 E2 依赖性病毒转录。BRG-1/hSNF2 的 ATP 酶活性对于有效的 E2 依赖性转录激活是必需的。瞬时 DNA 复制实验表明，hSNF5 和 BRG-1 增强了体内 HPV-18 DNA 的复制。显性负 hSNF5 和 BRG-1 ATP 酶突变体均抑制体内 E2 依赖性病毒转录和 E2 驱动的 HPV DNA 复制。酵母酿酒酵母 SNF5 敲除株中 HPV-18 E2 的转录激活功能缺陷的事实表明，SWI/SNF 复合物是 E2 转录激活功能所必需的。
这些结果表明，SWI/SNF 复合物通过与 E2 相互作用参与 HPV E2 驱动的转录和 DNA 复制。
