Cerutti M, Cerutti P, Devauchelle G
Laboratoire de Pathologie Comparée, Station de Recherches INRA-CNRS, Saint-Christol-Lez-Ales, France.
Virus Res. 1989 Apr;12(4):299-313. doi: 10.1016/0168-1702(89)90089-0.
Treatment of CIV particles with octylglucoside at high ionic strength leads to the solubilization of the inner viral membrane. Incubation of permissive cells (Cf124 cells) with vesicles obtained after dialysis of the detergent shows that this fraction is infectious. This infectivity, which is very low, could only be detected after two serial passages on permissive cells. This phenomenon is, however, reproducible. Isopycnic centrifugation analysis shows that some DNA cosediments with the vesicles. Extraction and purification of this DNA confirm the presence of a large DNA fragment of about 50.10(6) Da. Digestion with restriction endonucleases demonstrated that this DNA did not correspond to a particular fragment but to a population of DNA fragments of homogeneous size arising from various regions of the viral genome. Purified viral DNA was not infectious, the presence of DNA in the vesicles could not account therefore for their infectivity. Experiments of non-genetic reactivation of purified CIV DNA by UV-irradiated virus suggest that one (or several) structural component(s) of CIV particles must be involved in the first stages of the viral replication cycle. In addition, transfection of cells with large overlapping DNA fragments could generate infectious particles when the cells were superinfected with UV-irradiated virus. It can be supposed that the vesicle suspensions, which probably contain the reactivating factor, are composed of a population of vesicles which are all different in their DNA content. Infectivity of such suspensions would be the consequence of a recombination between large overlapping DNA fragments.
在高离子强度下用辛基葡糖苷处理CIV颗粒会导致病毒内膜溶解。将允许性细胞（Cf124细胞）与经去污剂透析后获得的囊泡一起孵育，结果表明该部分具有感染性。这种感染性非常低，只有在允许性细胞上连续传代两次后才能检测到。然而，这种现象是可重复的。等密度离心分析表明，一些DNA与囊泡一起沉降。对该DNA进行提取和纯化，证实存在一个约50×10⁶Da的大DNA片段。用限制性内切酶消化表明，该DNA并不对应于一个特定片段，而是对应于来自病毒基因组不同区域的大小均一的DNA片段群体。纯化的病毒DNA没有感染性，因此囊泡中DNA的存在不能解释它们的感染性。用紫外线照射的病毒对纯化的CIV DNA进行非遗传复活实验表明，CIV颗粒的一个（或几个）结构成分一定参与了病毒复制周期的最初阶段。此外，当细胞被紫外线照射的病毒超感染时，用大的重叠DNA片段转染细胞可产生感染性颗粒。可以推测，可能含有复活因子的囊泡悬液是由一群DNA含量各不相同的囊泡组成。这种悬液的感染性将是大的重叠DNA片段之间重组的结果。
