支持转录的无细胞系统,复制,描述了人类3型副流感病毒(HPF3)基因组RNA的核衣壳组装。感染的CV-1或BHK细胞的细胞质提取物催化整个HPF3基因组的转录,基因组RNA的复制,并将这种RNA组装成核壳样结构。新复制的RNA对微球菌核酸酶消化具有抗性,并且在CsCl梯度中稳定,表现出真正的HPF3核衣壳的密度。提取物分馏后,含核衣壳的颗粒部分合成了病毒mRNA。用可溶性蛋白质级分重建对于基因组RNA复制和核衣壳组装是必要的。
A cell-free system supporting transcription, replication, and nucleocapsid assembly of the genome RNA of human parainfluenza virus type 3 (HPF3) is described. Cytoplasmic extracts from infected CV-1 or BHK cells catalyzed the transcription of the entire HPF3 genome, the replication of genome RNA, and the assembly of this RNA into nucleocapsidlike structures. Newly replicated RNA was resistant to micrococcal nuclease digestion and was stable in CsCl gradients, exhibiting the density of authentic HPF3 nucleocapsids. After fractionation of the extracts, the nucleocapsid-containing pellet fraction synthesized viral mRNAs. Reconstitution with the soluble protein fraction was necessary for genome RNA replication and nucleocapsid assembly.