No single homologous repeat region is essential for DNA replication of the baculovirus Autographa californica multiple nucleopolyhedrovirus
No single homologous repeat region is essential for DNA replication of the baculovirus Autographa californica multiple nucleopolyhedrovirus
复制标题
DOI：
10.1099/vir.0.82384-0
复制
发表时间：
2007-01-01
影响因子：
3.8
通讯作者：
Wu, Yuntao
中科院分区：
文献类型：
--
作者：
Carstens, Eric B.;Wu, Yuntao
杆状病毒基因组内多个位置存在同源重复 (hr) 区域，因此人们推测它们代表 DNA 复制的起点。这一假设得到了瞬时复制测定的支持，其中携带 hrs 的质粒在病毒 DNA 复制存在的情况下进行复制。本研究通过生成一系列重组苜蓿银纹夜蛾多核多角体病毒，其中 lacZ 基因取代了 hr1、hr1a、hr2、hr3、hr4a 或 hr4b，研究了是否有特定的 hr 区域对于体内病毒 DNA 复制至关重要。此外，构建了双小时敲除病毒，其中hr2和hr3都被删除。这些敲除病毒的成功构建表明，没有特定区域对于病毒的产生是必需的。这些重组病毒的特征是出芽病毒的滴定、多种病毒特异性蛋白的表达以及感染后不同时间的病毒DNA的合成。结果表明，对于所有这些特性来说，每一小时都是可有可无的，并且没有任何一个区域对于细胞培养中的病毒复制是绝对必要的。多个起源区域的功能意义仍不清楚。
The presence of homologous repeat (hr) regions in multiple locations within baculovirus genomes has led to the hypothesis that they represent origins of DNA replication. This hypothesis has been supported by transient replication assays where plasmids carrying hrs replicated in the presence of virus DNA replication. This study investigated whether any specific hr region was essential for viral DNA replication in vivo, by generating a series of recombinant Autographa californica multiple nucleopolyhedrovirus where the lacZ gene replaced hr1, hr1a, hr2, hr3, hr4a or hr4b. In addition, a double-hr knockout virus was constructed where both hr2 and hr3 were deleted. The successful construction of these knockout viruses indicated that no specific region was essential for virus production. These recombinant viruses were characterized by titrations of budded virus, expression of a variety of virus-specific proteins and the synthesis of viral DNA at various times after infection. The results demonstrated that each hr was dispensable for all of these properties and that no single region was absolutely essential for virus replication in cell culture. The functional significance of multiple origin regions is still unclear.