Chen J X, Zhu X X, Silverstein S
Department of Microbiology, Columbia University, New York, New York 10032.
Virology. 1991 Jan;180(1):207-20. doi: 10.1016/0042-6822(91)90025-7.
In-frame codon insertion and deletion mutants were constructed in a plasmid containing the sequence that encodes ICP0, a transcriptional activator of herpes simplex virus type 1 (HSV-1). The effect of these mutations was analyzed in a transient expression assay using the promoters for, the IE-0 gene (an immediate early (alpha) gene), the thymidine kinase gene (an early (beta) gene), and the glycoprotein C gene (a late (gamma) gene) fused to reporter cassettes that encoded either beta-galactosidase or chloramphenicol acetyl transferase. Assays were performed in the presence or absence of a plasmid encoding ICP4, the major regulatory protein of HSV-1. Our results demonstrate that ICP0-mediated transactivation varied depending on the position of the insertion in the gene. One region of this protein was consistently shown to be required for full activation of each promoter examined either in the presence or in the absence of ICP4. This region overlaps with a cysteine-rich region and coincides with a transactivator domain identified in another extensive mutational analysis of this sequence. Analysis of the deletion mutants generated in this study demonstrated that the carboxy-terminal regions were required for activation in certain circumstances and that this varied depending on the promoter being assayed and the cell type in which the analysis was performed.
在一个含有编码单纯疱疹病毒1型（HSV-1）转录激活因子ICP0序列的质粒中构建了框内密码子插入和缺失突变体。使用与编码β-半乳糖苷酶或氯霉素乙酰转移酶的报告盒融合的IE-0基因（一个立即早期（α）基因）、胸苷激酶基因（一个早期（β）基因）和糖蛋白C基因（一个晚期（γ）基因）的启动子，在瞬时表达分析中分析了这些突变的影响。分析在存在或不存在编码HSV-1主要调节蛋白ICP4的质粒的情况下进行。我们的结果表明，ICP0介导的反式激活因基因中插入位置的不同而有所变化。该蛋白的一个区域始终被证明是在存在或不存在ICP4的情况下，对所检测的每个启动子进行完全激活所必需的。该区域与一个富含半胱氨酸的区域重叠，并且与在对该序列进行的另一项广泛突变分析中确定的反式激活结构域一致。对本研究中产生的缺失突变体的分析表明，在某些情况下，羧基末端区域是激活所必需的，并且这因所检测的启动子和进行分析的细胞类型而异。
