生物多样性 ›› 2001, Vol. 09 ›› Issue (3): 294-300.doi: 10.17520/biods.2001044

• 论文 • 上一篇    下一篇

RNA病毒基因组和转录复制多样性的分子基础

刘青珍, 李凌云, 齐义鹏, 杨复华   

  1. (武汉大学病毒研究所,  武汉 430072)
  • 收稿日期:2000-09-11 修回日期:2001-01-15 出版日期:2001-08-20
  • 通讯作者: 刘青珍

Molecular mechanism for transcription and replication of RNA virus

LIU Qing-Zhen, LI Ling-Yun, QI Yi-Peng, YANG Fu-Hua   

  1. Institute of Virology , Wuhan University , Wuhan  430072
  • Received:2000-09-11 Revised:2001-01-15 Online:2001-08-20
  • Contact: LIU Qing-Zhen

自然界中RNA病毒的种类和数量比DNA病毒多得多。根据基因组类型,RNA病毒可分为多种类型。许多研究者认为:存在于古细菌Myxobacteria 中、仅仅有一个逆转录酶基因的反转子(Retron)可能是所有病毒的祖先。进化的模式如下:反转子→反座子→反转录转座子→反转录病毒→副反转录病毒→DNA病毒。RNA病毒转录/复制在很多特征上与DNA病毒迥然不同。依赖于RNA的RNA聚合酶是RNA病毒转录/复制的主要催化剂。RNA病毒基因组转录和复制都从3′端poly(A)或类tRNA结构或其他结构起始,内部终止是转录,通读到5′末端终止是复制。RNA病毒的模板有正链病毒RNA模板、负链病毒RNA模板和全长正负链反基因组RNA模板。RNA模板的选择调控机制非常复杂,目前知之甚少。选择模板、RNA聚合酶与转录因子结合形成复制体是两种主要的调控方法。另外,5′UTR 和3′UTR也可以调控RNA病毒的转录。

RNA viruses are much more than DNA viruses in quantity and species in nature. It can be divided into many types of viruses according to genomic type. Recently , many researchers indicate that the ret ron existing in Myxobacteria , which carries only one reverse transcriptase gene , is the possible ancestor for all kinds of viruses , with the following evolution model : Retron →Ret roposon →Ret ransposon →Ret rovirus →Pararet rovirus →DNA viruses. It is very different between transcription/ replication of RNA virus and DNA virus genomes in many aspects. RNA-dependent RNA polymerase is the major catalyst for transcription/ replication. Initiation sites for RNA virus t ranscription/ replication are specific structures [poly (A) or tRNA] at 3′ terminal region. Internal stop results in transcription but reading through to 5′end resulting in replication. RNA viruses use the following four kinds of templates in transcription/ replication : ( + ) ssRNA template , ( - ) ssRNA template , ( + ) aRNA template , ( - ) aRNA template. The mechanism of selective regulation on RNA templates is very complex and the acknowledgements of the regulation mechanism are quite few up to now. Selecting template and the binding of transcription factors with RNA pol to form replicon are two major regulatory means. Besides promoter and transcription factors , 5′UTR and 3′UTR also regulate the transcription of RNA viruses.

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