Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institutes of Health, 33 North Drive, Building 33, Room 2E19A.2, Bethesda, MD 20892, USA.
J Virol. 2011 Nov;85(22):12067-72. doi: 10.1128/JVI.05559-11. Epub 2011 Aug 31.
Cleavage of the flavivirus prM protein by a cellular furin-like protease is a hallmark of virion maturation. While this cleavage is a required step in the viral life cycle, it can be inefficient. Virions that retain uncleaved prM may be infectious. We investigated whether cleavage by furin of prM on partially mature West Nile virus (WNV) during virus entry contributes to infectivity. Using quantitative assays of WNV infection, we found that virions incorporating considerable amounts of uncleaved prM protein were insensitive to treatment of cells with a potent inhibitor of furin activity. Thus, partially mature WNV does not require furin-like proteases for infectivity.
裂殖病毒的 prM 蛋白由细胞中的类弗林蛋白酶切割，这是病毒成熟的一个标志。虽然这种切割是病毒生命周期所必需的，但它可能效率低下。保留未切割的 prM 的病毒粒子可能具有传染性。我们研究了在病毒进入过程中，弗林蛋白酶对西尼罗河病毒（WNV）部分成熟的 prM 的切割是否有助于感染性。我们使用西尼罗河病毒感染的定量测定发现，含有大量未切割 prM 蛋白的病毒粒子对弗林活性的强效抑制剂处理细胞不敏感。因此，部分成熟的 WNV 不需要弗林样蛋白酶来感染。
