Nucleolin Interacts with the Feline Calicivirus 3′ Untranslated Region and the Protease-Polymerase NS6 and NS7 Proteins, Playing a Role in Virus Replication
Nucleolin Interacts with the Feline Calicivirus 3′ Untranslated Region and the Protease-Polymerase NS6 and NS7 Proteins, Playing a Role in Virus Replication
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DOI：
10.1128/jvi.01878-10
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发表时间：
2011-08-01
影响因子：
5.4
通讯作者：
Lorena Gutierrez-Escolano, Ana
中科院分区：
文献类型：
--
作者：
Cancio-Lonches, Clotilde;Yocupicio-Monroy, Martha;Lorena Gutierrez-Escolano, Ana
细胞蛋白在所有病毒的生命周期中起着许多重要作用。具体而言，宿主细胞核酸结合蛋白与正链RNA病毒的病毒组分相互作用并调节病毒翻译以及RNA复制。在这里，我们报告，核仁素，一种普遍存在的多功能核仁穿梭磷蛋白，与诺瓦克病毒和猫杯状病毒（FCV）基因组3'非翻译区（UTR）相互作用。核仁素还可以在体外与重组诺沃克病毒NS 6和NS 7（NS 6/7）形成复合物，并且可以与来自感染的猫肾细胞的猫杯状病毒（p76或NS 6/7）的类似蛋白共纯化。核仁素RNA水平或蛋白质在FCV感染过程中没有改变;然而，作为感染的结果，核仁素被认为是从核仁重新定位到核质，以及核周区域，在那里它与猫杯状病毒NS 6/7蛋白共定位。此外，核仁素抗体能够沉淀病毒RNA从猫杯状病毒感染的细胞，表明直接或间接协会的核仁素与病毒RNA在病毒复制。小干扰RNA（siRNA）介导的核仁素敲低导致CrFK细胞中的细胞病变效应和病毒产量减少。综上所述，这些结果表明，核仁素是一种核仁组分，与病毒RNA和NS 6/7相互作用，是猫杯状病毒复制所需的。
Cellular proteins play many important roles during the life cycle of all viruses. Specifically, host cell nucleic acid-binding proteins interact with viral components of positive-stranded RNA viruses and regulate viral translation, as well as RNA replication. Here, we report that nucleolin, a ubiquitous multifunctional nucleolar shuttling phosphoprotein, interacts with the Norwalk virus and feline calicivirus (FCV) genomic 3' untranslated regions (UTRs). Nucleolin can also form a complex in vitro with recombinant Norwalk virus NS6 and -7 (NS6/7) and can be copurified with the analogous protein from feline calicivirus (p76 or NS6/7) from infected feline kidney cells. Nucleolin RNA levels or protein were not modified during FCV infection; however, as a consequence of the infection, nucleolin was seen to relocalize from the nucleoli to the nucleoplasm, as well as to the perinuclear area where it colocalizes with the feline calicivirus NS6/7 protein. In addition, antibodies to nucleolin were able to precipitate viral RNA from feline calicivirus-infected cells, indicating a direct or indirect association of nucleolin with the viral RNA during virus replication. Small interfering RNA (siRNA)-mediated knockdown of nucleolin resulted in a reduction of the cytopathic effect and virus yield in CrFK cells. Taken together, these results demonstrate that nucleolin is a nucleolar component that interacts with viral RNA and NS6/7 and is required for feline calicivirus replication.