Dora S, Schwarz C, Knippers R
Fakultät für Biologie, Universität Konstanz, F.R.G.
J Mol Biol. 1989 Mar 5;206(1):81-90. doi: 10.1016/0022-2836(89)90525-1.
We have investigated the structure of simian virus 40 (SV40) DNA integrated into the genome of transformed mouse mKS-A cells. We have identified at least six independent integration units containing intact or truncated SV40 DNA sequences. One integration unit was isolated from a genomic mKS-A cell library and investigated by restriction enzyme analysis and partial nucleotide sequencing. This integration unit contains one apparently intact SV40 genome flanked on both sides by truncated versions of the SV40 genome. One of the flanking elements contains a large deletion in the SV40 "late" region and an abbreviated SV40 "early" region. This element was efficiently excised and mobilized after fusion of mKS-A to COS cells. The excision products invariably included the entire SV40 early region even though they were derived from an integrated element lacking this part of the SV40 genome. An analysis of this discrepancy led to the conclusion that the early region sequences were acquired by homologous recombination and, furthermore, that homologous excisional recombination was clearly preferred over non-homologous recombination.
我们研究了整合到转化的小鼠mKS - A细胞基因组中的猴病毒40（SV40）DNA的结构。我们鉴定出至少六个独立的整合单元，其中包含完整或截短的SV40 DNA序列。从基因组mKS - A细胞文库中分离出一个整合单元，并通过限制性内切酶分析和部分核苷酸测序进行研究。这个整合单元包含一个明显完整的SV40基因组，两侧是SV40基因组的截短版本。其中一个侧翼元件在SV40“晚期”区域有一个大的缺失，以及一个缩短的SV40“早期”区域。在mKS - A与COS细胞融合后，这个元件被有效地切除并转移。切除产物总是包含整个SV40早期区域，尽管它们来自一个缺乏SV40基因组这部分的整合元件。对这种差异的分析得出结论，早期区域序列是通过同源重组获得的，此外，同源切除重组明显优于非同源重组。
