Peden K W, Pipas J M
Howard Hughes Medical Institute Laboratory, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD.
Virus Genes. 1992 Apr;6(2):107-18. doi: 10.1007/BF01703060.
A series of amino-acid substitution mutants has been made with changes in the region of simian virus 40 large tumor antigen (T antigen) that is shared with the small tumor antigen (t antigen). Both single and multiple amino-acid replacements were obtained using the heteroduplex deletion loop method and sodium bisulfite as the mutagen. The mutants could be divided into five phenotypic classes on the basis of their biological properties: a) mutants whose changes did not affect their ability to propagate on permissive monkey cells, nor to transform nonpermissive rodent cells; b) mutants that were not viable, replicated their DNA to 5% or less of wild type, but were positive for transformation; c) mutants that were not viable, replicated their DNA to 5% or less of wild type, and were defective for transformation; and d) mutants that completely lost all three activities coordinately. In addition, one mutant with changes in this region, 5002, replicated its DNA to about 50% of wild type, had an impaired transformation activity, and produced virions at a level of about 4% that of wild type.
已经构建了一系列氨基酸替代突变体，这些突变体在猴病毒40大肿瘤抗原（T抗原）与小肿瘤抗原（t抗原）共有的区域发生了变化。使用异源双链缺失环法和亚硫酸氢钠作为诱变剂，获得了单氨基酸和多氨基酸替代突变体。根据其生物学特性，这些突变体可分为五个表型类别：a）其变化不影响它们在允许的猴细胞上繁殖的能力，也不影响它们转化非允许的啮齿动物细胞的能力的突变体；b）无活力的突变体，其DNA复制至野生型的5%或更低，但转化呈阳性；c）无活力的突变体，其DNA复制至野生型的5%或更低，并且转化存在缺陷；以及d）完全协调丧失所有三种活性的突变体。此外，在该区域发生变化的一个突变体5002，其DNA复制至野生型的约50%，转化活性受损，产生病毒粒子的水平约为野生型的4%。
