Sarafi T R, McBride A A
Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-0455, USA.
Virology. 1995 Aug 20;211(2):385-96. doi: 10.1006/viro.1995.1421.
The viral E1 and E2 proteins are required for replication of bovine papillomavirus type 1 DNA. Both proteins bind as a complex to the replication origin, which consists of an E1 binding site flanked on either side by E2 binding sites. The E1 protein has properties common to replication initiator proteins such as sequence-specific origin binding and DNA helicase activities. The E2 protein is a transcriptional transactivator that forms a complex with the E1 protein and enhances binding of E1 to the replication origin. We have mapped the regions of the E1 protein required for sequence-specific DNA binding, for cooperative binding with the E2 protein to the origin region, and for interaction with the E2 protein. These studies demonstrate that a region between amino acids 162 and 378 of the E1 protein is important for origin-specific DNA binding. The C-terminal half of the E1 protein is required in addition to the DNA binding domain (residues 162 to 605) for cooperative binding to the origin with the E2 protein. Binding studies confirmed that this region is also required for efficient complex formation with the E2 protein.
病毒E1和E2蛋白是牛乳头瘤病毒1型DNA复制所必需的。这两种蛋白以复合物形式结合到复制起点，该起点由一个E1结合位点和两侧的E2结合位点组成。E1蛋白具有复制起始蛋白的共同特性，如序列特异性起点结合和DNA解旋酶活性。E2蛋白是一种转录反式激活因子，它与E1蛋白形成复合物，并增强E1与复制起点的结合。我们已经确定了E1蛋白中序列特异性DNA结合、与E2蛋白协同结合到起点区域以及与E2蛋白相互作用所需的区域。这些研究表明，E1蛋白中氨基酸162至378之间的区域对于起点特异性DNA结合很重要。除了DNA结合结构域（残基162至605）外，E1蛋白的C末端一半对于与E2蛋白协同结合到起点也是必需的。结合研究证实，该区域对于与E2蛋白有效形成复合物也是必需的。
