Department of Plant Pathology, University of Kentucky, Plant Science Building, Lexington, KY 40546, USA.
Cell Host Microbe. 2010 Jan 21;7(1):74-81. doi: 10.1016/j.chom.2009.12.009. Epub 2010 Jan 20.
Viruses change rapidly due to genetic mutations, and viral RNA recombination in RNA viruses can lead to the emergence of drug-resistant or highly virulent strains. Here, we report that host Pmr1p, an ion pump that controls Ca2+/Mn2+ influx into the Golgi from the cytosol, affects the frequency of viral RNA recombination and the efficiency of replication. Inactivation of PMR1 leads to an approximately 160-fold increase in RNA recombination of Tomato bushy stunt virus (TBSV) in yeast, a model host. Expression of separation-of-function mutants of Pmr1p reveals that the ability of Pmr1p to control the Mn2+ concentration in the cytosol is a key factor in viral RNA recombination. Indeed, a high Mn2+ concentration in a cell-free TBSV replication system increases the recombination frequency, and knockdown of Ca2+/Mn2+ exporters in plants increases virus replication and RNA recombination. Thus, a conserved host protein could affect the adaptive evolution of RNA viruses.
病毒由于基因突变而迅速变化，而 RNA 病毒中的病毒 RNA 重组会导致耐药性或高毒力菌株的出现。在这里，我们报告说，宿主 Pmr1p 是一种离子泵，可控制细胞质中 Ca2+/Mn2+流入高尔基体，它会影响病毒 RNA 重组的频率和复制效率。PMR1 的失活会导致番茄丛矮病毒（TBSV）在酵母这一模型宿主中的 RNA 重组频率增加约 160 倍。Pmr1p 的功能分离突变体的表达表明，Pmr1p 控制细胞质中 Mn2+浓度的能力是病毒 RNA 重组的关键因素。事实上，在无细胞 TBSV 复制系统中，较高的 Mn2+浓度会增加重组频率，而植物中 Ca2+/Mn2+外排器的敲低会增加病毒复制和 RNA 重组。因此，一种保守的宿主蛋白可能会影响 RNA 病毒的适应性进化。
