Jurgens Christy K, Barton David J, Sharma Nidhi, Morasco B Joan, Ogram Sushma A, Flanegan James B
Department of Biochemistry and Molecular Biology, University of Florida, College of Medicine, Gainesville, 32610-0245, USA.
Virology. 2006 Feb 20;345(2):346-57. doi: 10.1016/j.virol.2005.09.067. Epub 2005 Nov 17.
Poliovirus 2A(pro) is required for the inhibition of host cell protein synthesis and efficient viral replication. We investigated the role of 2A(pro) in regulating viral RNA stability, translation and replication in HeLa S10 reactions. The protease activity of 2A(pro) or its polyprotein precursors, 2AB or P2, was required to increase the stability of viral RNA and prolong translation. Since other viral proteins were not required for the observed effects of 2A(pro), it is likely that a cellular protein(s) modified by 2A(pro) mediated these effects on stability and translation. In addition, the protease activity of 2A(pro) stimulated negative-strand initiation by approximately five-fold but had no effect on positive-strand initiation. The 2A(pro) stimulation of negative-strand synthesis was independent of its effect on stability and translation. These findings further extend the previously known functions of protein 2A(pro) to include its role in increasing RNA stability, prolonging translation and stimulating negative-strand synthesis.
脊髓灰质炎病毒2A蛋白酶(2A(pro))是抑制宿主细胞蛋白质合成和高效病毒复制所必需的。我们研究了2A(pro)在HeLa S10反应中调节病毒RNA稳定性、翻译和复制的作用。2A(pro)或其多蛋白前体2AB或P2的蛋白酶活性是增加病毒RNA稳定性和延长翻译所必需的。由于观察到的2A(pro)的作用不需要其他病毒蛋白,因此很可能是被2A(pro)修饰的一种或多种细胞蛋白介导了这些对稳定性和翻译的影响。此外,2A(pro)的蛋白酶活性将负链起始刺激了约五倍,但对正链起始没有影响。2A(pro)对负链合成的刺激与其对稳定性和翻译的影响无关。这些发现进一步扩展了先前已知的蛋白质2A(pro)的功能,包括其在增加RNA稳定性、延长翻译和刺激负链合成中的作用。