Mobility of endogenous ecotropic murine leukemia viral genomes within mouse chromosomal DNA and integration of a mink cell focus-forming virus-type recombinant provirus in the germ line
Mobility of endogenous ecotropic murine leukemia viral genomes within mouse chromosomal DNA and integration of a mink cell focus-forming virus-type recombinant provirus in the germ line
复制标题
内源性嗜食性鼠白血病病毒基因组在小鼠染色体DNA中的迁移性以及水貂细胞病灶形成病毒型重组原病毒在种系中的整合
作者：
Wim Quint;H. V. D. Putten;Frans Janssen;Anton;'. Berns
对低度和高度白血病小鼠品系 DNA 中内源性亲食性 Akv 原病毒的表征表明，在种系中整合的每个单倍体基因组等价物中存在 1 至 6 个 Akv 基因组拷贝。迄今为止分析的低度白血病毒株仅含有一份完整的 Akv 前病毒 DNA 拷贝。尽管遗传相关的菌株通常在同一染色体位点携带 Akv 原病毒基因，但不同菌株的整合位点有所不同。 AKR 小鼠的不同亚系显示出不同数量（2 到 6 个）的 Akv 基因组。在所有亚株中，一个 Akv 基因组存在于相同的染色体位点中；该基因座可能包含祖基因组。密切相关的亚株在共同位点上整合了多个 Akv 原病毒 DNA。 Akv 基因组在 AKR/FuRdA 菌株种系中的积累可能是独立整合事件的结果，因为 Akv 阴性 129 菌株的回交研究显示所有六个原病毒基因座的随机分离。 AKR/Cnb 菌株在种系中携带重组原病毒。这种原病毒在结构上类似于 AKR 水貂细胞病灶形成病毒，后者是在白血病发生过程中通过体细胞重组产生的。因此，Akv 前病毒 DNA 的种系扩增最有可能是通过循环病毒感染胚胎细胞而发生的。
Characterization of endogenous ecotropic Akv proviruses in DNA of low and high leukemic mouse strains revealed the presence of one to six copies of the Akv genome per haploid genome equivalent integrated in the germ line. Low leukemic strains analyzed so far contained only one complete copy of the Akv proviral DNA. The site of integration varied among strains, although genetically related strains often carried the Akv proviral gene in the same chromosomal site. The different substrains of the AKR mouse displayed the presence of variable numbers (two to six) of Akv genomes. In all substrains one Akv genome was present in an identical chromosomal site; this locus probably comprised the progenitor genome. Closely related substrains had several Akv proviral DNAs integrated in common sites. The accumulation of Akv genomes in the germ line of the AKR/FuRdA strain is likely the result of independent integration events, since backcross studies with the Akv-negative 129 strain showed random segregation of all six proviral loci. The AKR/Cnb strain carried a recombinant provirus in the germ line. This provirus resembled in structure the AKR mink cell focus-forming viruses, which are generated by somatic recombination during leukemogenesis. Therefore, the germ-line amplification of Akv proviral DNAs occurs most likely through infection of embryonic cells by circulating virus.