Herold J, Andino R
Department of Microbiology and Immunology, University of California, San Francisco, 94143, USA.
Mol Cell. 2001 Mar;7(3):581-91. doi: 10.1016/s1097-2765(01)00205-2.
The mechanisms and factors involved in the replication of positive stranded RNA viruses are still unclear. Using poliovirus as a model, we show that a long-range interaction between ribonucleoprotein (RNP) complexes formed at the ends of the viral genome is necessary for RNA replication. Initiation of negative strand RNA synthesis requires a 3' poly(A) tail. Strikingly, it also requires a cloverleaf-like RNA structure located at the other end of the genome. An RNP complex formed around the 5' cloverleaf RNA structure interacts with the poly(A) binding protein bound to the 3' poly(A) tail, thus linking the ends of the viral RNA and effectively circularizing it. Formation of this circular RNP complex is required for initiation of negative strand RNA synthesis. RNA circularization may be a general replication mechanism for positive stranded RNA viruses.
正链RNA病毒复制所涉及的机制和因素仍不清楚。以脊髓灰质炎病毒为模型，我们发现病毒基因组末端形成的核糖核蛋白（RNP）复合物之间的长程相互作用对于RNA复制是必要的。负链RNA合成的起始需要一个3' 聚腺苷酸尾。引人注目的是，它还需要位于基因组另一端的类似三叶草的RNA结构。围绕5' 三叶草RNA结构形成的RNP复合物与结合在3' 聚腺苷酸尾上的聚腺苷酸结合蛋白相互作用，从而连接病毒RNA的两端并有效地使其环化。这种环状RNP复合物的形成是负链RNA合成起始所必需的。RNA环化可能是正链RNA病毒的一种普遍复制机制。
