Klikova M, Rhee S S, Hunter E, Ruml T
Department of Biochemistry and Microbiology, Institute of Chemical Technology, Prague, Czech Republic.
J Virol. 1995 Feb;69(2):1093-8. doi: 10.1128/JVI.69.2.1093-1098.1995.
The capsid precursor protein (Gag) of Mason-Pfizer monkey virus, the prototype type D retrovirus, has been expressed to high levels in bacteria under the control of the phage T7 promoter. Electron microscopic studies of induced cells revealed the assembly of capsid-like structures within inclusion bodies that formed at the poles of the cells 6 h after induction with isopropyl-beta-D-thiogalactopyranoside (IPTG). The inclusion bodies and enclosed capsid-like structures were solubilized completely in 8 M urea, but following renaturation, we observed assembly in vitro of capsid-like structures that demonstrated apparent icosahedral symmetry. These results demonstrate for the first time that retroviral capsid precursors have the propensity to self-assemble in vitro and point to new approaches for the analysis of retroviral assembly and structure.
原型D型逆转录病毒——梅森- Pfizer猴病毒的衣壳前体蛋白（Gag），已在噬菌体T7启动子的控制下在细菌中高水平表达。对诱导细胞的电子显微镜研究显示，在用异丙基-β-D-硫代半乳糖苷（IPTG）诱导6小时后，在细胞两极形成的包涵体内组装了衣壳样结构。包涵体和封闭的衣壳样结构在8 M尿素中完全溶解，但复性后，我们观察到体外组装的衣壳样结构呈现出明显的二十面体对称性。这些结果首次证明逆转录病毒衣壳前体在体外具有自组装的倾向，并为逆转录病毒组装和结构的分析指明了新方法。
