Muzyczka N
Gene. 1979 Jun;6(2):107-22. doi: 10.1016/0378-1119(79)90066-0.
To test the suitability of simian virus 40 (SV40) DNA as a vector for inserting DNA segments into the chromosomes of mammalian cells, an EcoRI-A fragment of bacteriophage lambda DNA was covalently joined to a fragment of SV40 DNA and used to transform mouse cells in culture. Three independent, morphologically transformed clones were obtained that were positive for SV40 T-antigen by immunofluorescence staining. DNA from each transformant was examined by restriction enzyme analysis and found to contain both lambda and SV40 sequences. Co-migration of some fragments containing lambda and SV40 sequences following digestion of transformed cell DNA by each of four different restriction enzymes indicated that part of the retained lambda and SV40 DNA was linked in two of the three lines. In the third line, however, none of the restriction fragments had both lambda and SV40 sequences. Although the presence of non-integrated lambda DNA was not excluded, at least some of the lambda DNA appeared to be linked to host cell DNA. Results of digestion by EcoRI suggested that in some cases the transforming linear molecule had probably circularized prior to integration.
为了测试猿猴病毒40（SV40）DNA作为将DNA片段插入哺乳动物细胞染色体的载体的适用性，将噬菌体λDNA的EcoRI - A片段与SV40 DNA片段共价连接，并用于转化培养中的小鼠细胞。通过免疫荧光染色获得了三个独立的、形态学上转化的克隆，它们对SV40 T抗原呈阳性。通过限制性酶切分析检查每个转化体的DNA，发现其含有λ和SV40序列。在用四种不同的限制性酶消化转化细胞DNA后，一些含有λ和SV40序列的片段的共迁移表明，在三个细胞系中的两个中，保留的部分λ和SV40 DNA是相连的。然而，在第三个细胞系中，没有一个限制性片段同时含有λ和SV40序列。虽然不排除存在未整合的λDNA，但至少一些λDNA似乎与宿主细胞DNA相连。EcoRI消化的结果表明，在某些情况下，转化的线性分子可能在整合之前已经环化。
