Fischer N, Enssle J, Müller J, Rethwilm A, Niewiesk S
Institut für Virologie und Immunbiologie, Universität Würzburg, Germany.
AIDS Res Hum Retroviruses. 1997 Apr 10;13(6):517-21. doi: 10.1089/aid.1997.13.517.
We report the generation of recombinant vaccinia viruses (VVs) expressing the gag, pol, bel-1, and bet open reading frames of human foamy virus (HFV), and the establishment of a transient, VV-T7 RNA polymerase-directed expression system for the HFV env gene. The correct expression of the HFV proteins was demonstrated by radioimmunoprecipitation using monospecific rabbit antisera, by analysis of the subcellular distribution (for VVgag, VVpol, VVbel-1, and VVbet), and by the ability to induce syncytium formation (for the env expression system). The HFV pol gene was successfully expressed using its own ATG start codon. Foamy viruses are regarded as retroviruses with intracytoplasmatic capsid assembly. However, when VVgag and VVpol were used to study the HFV Gag-Pol protein interaction and particle formation, no HFV capsid structures were observed in singly or doubly infected cells. In addition, no cleavage of the Pr74gag precursor molecule by the pol-encoded protease was detected in doubly infected cells. Our results indicate that foamy virus particle assembly is fundamentally different from that of other retroviruses.
我们报告了表达人泡沫病毒（HFV）的gag、pol、bel-1和bet开放阅读框的重组痘苗病毒（VVs）的产生，以及建立了一个用于HFV env基因的瞬时、痘苗病毒-T7 RNA聚合酶指导的表达系统。通过使用单特异性兔抗血清的放射免疫沉淀、亚细胞分布分析（针对VVgag、VVpol、VVbel-1和VVbet）以及诱导合胞体形成的能力（针对env表达系统），证明了HFV蛋白的正确表达。HFV pol基因利用其自身的ATG起始密码子成功表达。泡沫病毒被认为是具有胞质内衣壳组装的逆转录病毒。然而，当使用VVgag和VVpol研究HFV Gag-Pol蛋白相互作用和颗粒形成时，在单感染或双感染细胞中均未观察到HFV衣壳结构。此外，在双感染细胞中未检测到pol编码的蛋白酶对Pr74gag前体分子的切割。我们的结果表明，泡沫病毒颗粒组装与其他逆转录病毒有根本不同。
