Oglesbee M, Ringler S, Krakowka S
Department of Veterinary Pathobiology, The Ohio State University, Columbus 43210.
J Gen Virol. 1990 Jul;71 ( Pt 7):1585-90. doi: 10.1099/0022-1317-71-7-1585.
Cytoplasmic nucleocapsid (NC) isolated from Vero (V) cells infected in the logarithmic phase of growth with Onderstepoort canine distemper virus consists of light-NC (L-NC) and dense-NC (D-NC), encapsidating full-length genomic RNA, and defective-NC (Df-NC), encapsidating variably truncated RNAs. The 70K host cell protein constituent of L-NC and Df-NC was shown to be a member of the 70K heat-shock protein (70K hsp) family. Specifically, 72K hsp is associated with L-NC, and 72K and 73K hsp are associated with Df-NC. Variable L-NC production by three different Vero cell sublines was compared to cellular 70K hsp levels. V141 supported the highest level of L-NC production and expressed high basal levels of 70K hsp in uninfected cells. These high basal levels correspond to a large distribution of log phase V141s in the S phase of the cell cycle. V138-L and V138-H cells produced lower amounts of L-NC and exhibited similar low basal levels of 70K hsp expression, corresponding to low percentages of log phase cells in the S phase cell cycle compartment. Heat shock was effective in inducing L-NC expression in V138-H, which otherwise produced D-NC. Similar cell subline differences in L-NC production were obtained for eight different virus pools derived from the same plaque-purified parental stock. Enhanced biological activity was associated with L-NC based on correlation between L-NC production, viral titre, and plaque areas measured over infected cells.
从在生长对数期感染了 Onderstepoort 犬瘟热病毒的 Vero（V）细胞中分离出的细胞质核衣壳（NC）由轻核衣壳（L-NC）和致密核衣壳（D-NC）组成，它们包裹着全长基因组 RNA，还有缺陷核衣壳（Df-NC），包裹着可变截短的 RNA。L-NC 和 Df-NC 的 70K 宿主细胞蛋白成分被证明是 70K 热休克蛋白（70K hsp）家族的成员。具体而言，72K hsp 与 L-NC 相关，72K 和 73K hsp 与 Df-NC 相关。比较了三种不同 Vero 细胞亚系产生的可变 L-NC 与细胞 70K hsp 水平。V141 支持最高水平的 L-NC 产生，并且在未感染细胞中表达高水平的基础 70K hsp。这些高基础水平对应于细胞周期 S 期对数期 V141 的大量分布。V138-L 和 V138-H 细胞产生的 L-NC 量较低，并且表现出相似的低基础 70K hsp 表达水平，对应于 S 期细胞周期隔室中对数期细胞的低百分比。热休克有效地诱导了 V138-H 中 L-NC 的表达，否则该细胞系产生 D-NC。对于来自同一噬斑纯化亲本毒株的八个不同病毒库，在 L-NC 产生方面也获得了类似的细胞亚系差异。基于 L-NC 产生、病毒滴度和在感染细胞上测量的噬斑面积之间的相关性，增强的生物学活性与 L-NC 相关。
