Lavi S, Winocour E
J Virol. 1972 Feb;9(2):309-16. doi: 10.1128/JVI.9.2.309-316.1972.
The synthesis of closed circular simian virus 40 (SV40) deoxyribonucleic acid (DNA) containing sequences homologous to host cell DNA depends upon the conditions under which the cells are infected. When BS-C-1 monkey cells were infected with non-plaque-purified virus at low multiplicity of infection [MOI, 0.032 plaque-forming units (PFU)/cell], little, if any, of the SV40 DNA extracted from the infected cells hybridized to host DNA; but when increasingly higher multiplicities were used (in the range 0.16 to 3,000 PFU/cell), an increasingly greater amount of the extracted SV40 DNA hybridized to host DNA. The same effect was observed when the closed circular SV40 DNA was extracted from purified virions (grown at low and high MOI) rather than from the infected cell complex. When the cells were infected at high MOI with plaque-purified virus (11 viral clones were tested), none of the SV40 DNA extracted from the cells hybridized detectably with host cell DNA. However, plaque-purified virus that was serially passaged, undiluted, induced the synthesis of virus DNA which again showed extensive homology to host DNA. It is suggested that, under certain circumstances, recombination occurs between viral and host DNA during lytic infection which results in the incorporation of host DNA sequences into closed circular SV40 DNA.
含有与宿主细胞DNA同源序列的闭环猴病毒40（SV40）脱氧核糖核酸（DNA）的合成取决于细胞被感染的条件。当BS - C - 1猴细胞以低感染复数[MOI，0.032噬斑形成单位（PFU）/细胞]感染未经噬斑纯化的病毒时，从感染细胞中提取的SV40 DNA与宿主DNA杂交的很少（如果有的话）；但是当使用越来越高的感染复数（在0.16至3000 PFU/细胞范围内）时，提取的SV40 DNA与宿主DNA杂交的量越来越大。当从纯化的病毒颗粒（在低和高MOI下生长）而不是从感染细胞复合物中提取闭环SV40 DNA时，也观察到了相同的效果。当细胞以高MOI用噬斑纯化的病毒感染时（测试了11个病毒克隆），从细胞中提取的SV40 DNA均未与宿主细胞DNA发生可检测的杂交。然而，连续传代、未稀释的噬斑纯化病毒诱导了病毒DNA的合成，该病毒DNA再次显示出与宿主DNA的广泛同源性。有人提出，在某些情况下，在裂解感染期间病毒DNA与宿主DNA之间会发生重组，这导致宿主DNA序列掺入闭环SV40 DNA中。
