Frolov I, Hoffman T A, Prágai B M, Dryga S A, Huang H V, Schlesinger S, Rice C M
Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110-1093, USA.
Proc Natl Acad Sci U S A. 1996 Oct 15;93(21):11371-7. doi: 10.1073/pnas.93.21.11371.
Alphaviruses are positive-strand RNA viruses that can mediate efficient cytoplasmic gene expression in insect and vertebrate cells. Through recombinant DNA technology, the alphavirus RNA replication machinery has been engineered for high-level expression of heterologous RNAs and proteins. Amplification of replication-competent alpha-virus RNAs (replicons) can be initiated by RNA or DNA transfection and a variety of packaging systems have been developed for producing high titers of infectious viral particles. Although normally cytocidal for vertebrate cells, variants with adaptive mutations allowing noncytopathic replication have been isolated from persistently infected cultures or selected using a dominant selectable marker. Such mutations have been mapped and used to create new alphavirus vectors for noncytopathic gene expression in mammalian cells. These vectors allow long-term expression at moderate levels and complement previous vectors designed for short-term high-level expression. Besides their use for a growing number of basic research applications, recombinant alphavirus RNA replicons may also facilitate genetic vaccination and transient gene therapy.
甲病毒是正链RNA病毒，能够在昆虫和脊椎动物细胞中介导高效的细胞质基因表达。通过重组DNA技术，甲病毒RNA复制机制已被改造用于高水平表达异源RNA和蛋白质。具有复制能力的甲病毒RNA（复制子）的扩增可通过RNA或DNA转染启动，并且已经开发了多种包装系统用于生产高滴度的感染性病毒颗粒。虽然甲病毒通常对脊椎动物细胞具有细胞毒性，但已从持续感染的培养物中分离出具有允许非细胞病变复制的适应性突变的变体，或使用显性选择标记进行选择。这些突变已被定位，并用于创建新的甲病毒载体，用于在哺乳动物细胞中进行非细胞病变基因表达。这些载体允许中等水平的长期表达，并补充了以前设计用于短期高水平表达的载体。除了用于越来越多的基础研究应用外，重组甲病毒RNA复制子还可能促进基因疫苗接种和瞬时基因治疗。
