Rassart E, Sankar-Mistry P, Lemay G, DesGroseillers L, Jolicoeur P
J Virol. 1983 Feb;45(2):565-75. doi: 10.1128/JVI.45.2.565-575.1983.
We previously reported the establishment of several lymphoid cell lines from X-ray-induced thymomas of C57BL/Ka mice, and all, except one, produce retroviruses (P. Sankar-Mistry and P. Jolicoeur, J. Virol.35:270-275, 1980). Biological characterization of five of these new primary radiation leukemia viruses (RadLVs) indicated that they had a B-tropic, fibrotropic, and ecotropic host range and were leukemogenic when reinjected into C57BL/Ka newborn mice. The leukemogenic potential of one isolate (G(6)T(2)) was further assessed and shown to be retained after prolonged passaging on fibroblasts in vitro. Restriction endonuclease analysis of the DNA of four of our new RadLV isolates (G(6)T(2), Ti-7, Ti-8, and Ti-9) revealed that G(6)T(2) and Ti-7 murine leukemia virus (MuLV) genomes had identical restriction maps, whereas Ti-8 and Ti-9 genomes were different from each other and from the G(6)T(2) and Ti-7 genomes. The physical maps of these genomes were similar to that of known ecotropic MuLV genomes (including the C57BL/Ka endogenous ecotropic MuLV) within their long terminal repeats, env, the right portion of pol, and the left portion of gag. However, a region covering the end of gag and the beginning of pol was different and showed several similarities with xenotropic MuLV genomes of BALB/c, AKR, and C58 mice previously mapped. Our results suggest that these primary RadLV genomes are recombinants between the parental ecotropic MuLV genome and a nonecotropic (xenotropic) sequence. This nonecotropic gag-pol region might be important in conferring the leukemogenic potential to these isolates. Therefore, these RadLVs appear to form a new class of leukemogenic recombinant MuLVs recovered from leukemic tissues of mice. They appear to be distinct from the recombinant AKR mink cell focus-inducing MuLVs which have a dual-tropic host range and harbor xenotropic env sequences. To further study the leukemogenic potential of these RadLVs, the genome of one of them (G(6)T(2)) was cloned in Charon 21A as an infectious molecule.
我们之前报道了从C57BL/Ka小鼠经X射线诱导产生的胸腺瘤中建立了几种淋巴样细胞系，除一个细胞系外，其他所有细胞系都能产生逆转录病毒（P. 桑卡尔 - 米斯特里和P. 若利厄尔，《病毒学杂志》35:270 - 275, 1980）。对其中五种新的原发性辐射白血病病毒（RadLVs）进行生物学特性分析表明，它们具有B嗜性、纤维嗜性和嗜亲性宿主范围，并且重新注射到C57BL/Ka新生小鼠体内时具有致白血病性。对一种分离株（G(6)T(2)）的致白血病潜力进行了进一步评估，结果表明在体外成纤维细胞上长时间传代后其致白血病潜力得以保留。对我们新的四种RadLV分离株（G(6)T(2)、Ti - 7、Ti - 8和Ti - 9）的DNA进行限制性内切酶分析发现，G(6)T(2)和Ti - 7小鼠白血病病毒（MuLV）基因组具有相同的限制性图谱，而Ti - 8和Ti - 9基因组彼此不同，也与G(6)T(2)和Ti - 7基因组不同。这些基因组的物理图谱在其长末端重复序列、env、pol的右侧部分和gag的左侧部分与已知的嗜亲性MuLV基因组（包括C57BL/Ka内源性嗜亲性MuLV）相似。然而，一个覆盖gag末端和pol起始部分的区域不同，并且与之前绘制图谱的BALB/c、AKR和C58小鼠的异嗜性MuLV基因组有几个相似之处。我们的结果表明，这些原发性RadLV基因组是亲本嗜亲性MuLV基因组与一个非嗜亲性（异嗜性）序列之间的重组体。这个非嗜亲性的gag - pol区域可能在赋予这些分离株致白血病潜力方面很重要。因此，这些RadLVs似乎形成了一类从小鼠白血病组织中分离出的新型致白血病重组MuLVs。它们似乎与具有双嗜性宿主范围且含有异嗜性env序列的重组AKR水貂细胞灶诱导MuLVs不同。为了进一步研究这些RadLVs的致白血病潜力，其中一种（G(6)T(2)）的基因组作为感染性分子被克隆到Charon 21A中。
