Kemble G W, Mocarski E S
Department of Microbiology and Immunology, Stanford University School of Medicine, California 94305.
J Virol. 1989 Nov;63(11):4715-28. doi: 10.1128/JVI.63.11.4715-4728.1989.
The human cytomegalovirus (CMV) a sequence has significant homology to two regions, pac-1 and pac-2, within the a sequence of herpes simplex virus type 1 (HSV-1). Both regions have been shown to be important cis-acting signals in HSV-1 genome maturation. We have demonstrated that a small fragment from within the CMV a sequence, containing the pac-1 and pac-2 motifs, carries all of the signals necessary for generation of genomic termini and for inversion. These observations indicated that the function of these highly conserved sequence motifs was similar in CMV and HSV-1. We have identified and partially purified a host cell protein with affinity for the sequence 5'-GGCGGCGGCGCATAAAA-3' within CMV pac-2. This partially purified protein has an apparent molecular weight of 89,000 under denaturing conditions and could be renatured after sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggesting that the capacity to bind DNA was the property of a single polypeptide chain. This activity was found in a wide variety of human cell lines, including those that are permissive as well as those that are nonpermissive for CMV growth, but not in cell lines from monkey, mouse, or drosophila origins. Our work implicates a host cell protein in a sequence function.
人类巨细胞病毒（CMV）的α序列与单纯疱疹病毒1型（HSV-1）的α序列中的两个区域pac-1和pac-2具有显著的同源性。这两个区域在HSV-1基因组成熟过程中已被证明是重要的顺式作用信号。我们已经证明，来自CMVα序列内的一个小片段，包含pac-1和pac-2基序，携带了产生基因组末端和进行倒位所需的所有信号。这些观察结果表明，这些高度保守的序列基序在CMV和HSV-1中的功能相似。我们已经鉴定并部分纯化了一种对CMV pac-2内的5'-GGCGGCGGCGCATAAAA-3'序列具有亲和力的宿主细胞蛋白。这种部分纯化的蛋白在变性条件下的表观分子量为89,000，并且在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳后可以复性，这表明结合DNA的能力是单个多肽链的特性。在多种人类细胞系中都发现了这种活性，包括那些对CMV生长允许的细胞系以及那些对CMV生长不允许的细胞系，但在源自猴、小鼠或果蝇的细胞系中未发现。我们的工作表明一种宿主细胞蛋白参与了序列功能。
