Stow N D, McMonagle E C, Davison A J
Nucleic Acids Res. 1983 Dec 10;11(23):8205-20. doi: 10.1093/nar/11.23.8205.
A 535 base pair DNA fragment which maps entirely within the IRS/TRS regions of the herpes simplex virus type 1 (HSV-1) genome and contains all the cis-acting signals necessary for it to function as an origin of viral DNA replication has previously been identified (N.D. Stow and E.C. McMonagle, Virology, in press). When BHK cells were transfected with circular plasmid molecules containing cloned copies of this DNA fragment, and superinfected with wt HSV-1 as helper, amplification of the input plasmid was detected. Two observations indicated that the amplified DNA was not packaged into virus particles. Firstly, when the transfected cells were disrupted the amplified DNA was susceptible to digestion by added DNase, and secondly, it was not possible to further propagate the DNA when virus from the cells was passaged. Fragments from the joint region and from both termini of the viral genome were inserted into origin-containing plasmids and the resulting constructs analysed. In all cases the inserted fragment allowed the amplified DNA to be further passaged, and a proportion to become resistant to digestion with DNase. These observations suggest that signals required for the encapsidation of HSV-1 DNA are located within DNA sequences shared by the inserted fragments and therefore lie within the reiterated 'a' sequence of the viral genome.
一个535个碱基对的DNA片段，其完全定位在单纯疱疹病毒1型（HSV-1）基因组的内部重复序列/末端重复序列区域内，并且包含其作为病毒DNA复制起点发挥功能所必需的所有顺式作用信号，此前已被鉴定出来（N.D.斯托和E.C.麦克莫纳格尔，《病毒学》，即将出版）。当用含有该DNA片段克隆拷贝的环状质粒分子转染BHK细胞，并以野生型HSV-1作为辅助病毒进行超感染时，检测到输入质粒的扩增。两项观察结果表明，扩增的DNA没有被包装到病毒颗粒中。首先，当转染的细胞被破坏时，扩增的DNA易于被添加的DNA酶消化，其次，当细胞中的病毒传代时，不可能进一步扩增该DNA。将来自病毒基因组连接区域和两个末端的片段插入含起点的质粒中，并对所得构建体进行分析。在所有情况下，插入的片段都能使扩增的DNA进一步传代，并且有一部分对DNA酶消化具有抗性。这些观察结果表明，HSV-1 DNA包装所需的信号位于插入片段共有的DNA序列内，因此位于病毒基因组的重复“a”序列内。
