Joseph D R
Arch Virol. 1983;78(3-4):255-66. doi: 10.1007/BF01311320.
Analyses of Hirt extracts from endogeneous murine leukemia virus (MuLV)-infected cells revealed the presence of 9-kbp linear DNA and two superhelical forms with one or two tandem copies of the long terminal repeat (LTR). In contrast, cells that were infected with AKR MCF247 MuLV yielded two major linear forms of 9.0 and 8.4 kbp and one discrete superhelical DNA. In addition, there was a heterogeneous population of superhelical DNAs that were larger and smaller than the major superhelical DNA species. Restriction endonuclease treatment of purified linear and superhelical DNAs have revealed that MCF247 MuLV unintegrated viral DNA is very heterogeneous. Evidence is presented that there are at least two linear DNAs; one is 9-kbp full-length linear DNA, whereas the other major form contains a 0.6 to 0.7-kbp deletion in the envelope gene adjacent to the right LTR. In addition, there are two size classes of the LTR in at least the full-length linear DNA. The major superhelical DNA species is a 8.4-kbp form which contains one copy of the LTR. Other heterogeneous superhelical DNAs appear to contain env-gene deletions or partially deleted copies of a tandem LTR region.
对来自内源性鼠白血病病毒（MuLV）感染细胞的Hirt提取物进行分析，发现存在9千碱基对（kbp）的线性DNA以及两种超螺旋形式，其中一种或两种带有长末端重复序列（LTR）的串联拷贝。相比之下，感染AKR MCF247 MuLV的细胞产生了两种主要的线性形式，分别为9.0 kbp和8.4 kbp，以及一种离散的超螺旋DNA。此外，还存在一群异质性的超螺旋DNA，其大小比主要的超螺旋DNA种类大或小。对纯化的线性和超螺旋DNA进行限制性内切酶处理表明，MCF247 MuLV未整合的病毒DNA非常异质。有证据表明至少存在两种线性DNA；一种是9 kbp的全长线性DNA，而另一种主要形式在与右LTR相邻的包膜基因中含有0.6至0.7 kbp的缺失。此外，至少在全长线性DNA中存在两种大小类别的LTR。主要的超螺旋DNA种类是一种8.4 kbp的形式，其中包含一个LTR拷贝。其他异质性超螺旋DNA似乎包含env基因缺失或串联LTR区域的部分缺失拷贝。
