Cholesterol removal by methyl-β-cyclodextrin inhibits poliovirus entry
Cholesterol removal by methyl-β-cyclodextrin inhibits poliovirus entry
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DOI：
10.1128/jvi.78.1.33-41.2004
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发表时间：
2004-01-01
影响因子：
5.4
通讯作者：
Chow, M
中科院分区：
文献类型：
--
作者：
Danthi, P;Chow, M
在与脊髓灰质炎病毒受体（PVR）结合后，脊髓灰质炎病毒160S颗粒发生构象转变，产生135S颗粒，135S颗粒被认为是病毒进入过程中的中间体。135S颗粒通过VP1的N末端和十四酰化的VP4蛋白的暴露与宿主细胞膜相互作用，而基因组RNA成功递送至细胞质需要这些结构域与身份未知的细胞膜相互作用。由于质膜中的去垢剂不溶性微区（DIMS）已被证明在其他小核糖核酸病毒的进入过程中很重要，因此确定脊髓灰质炎病毒在病毒进入过程中是否同样需要DIMS是很有意义的。我们在此表明，甲基-β-环糊精（MβCD）通过消耗细胞中的胆固醇破坏DIMS，抑制病毒感染，并且通过部分恢复细胞中的胆固醇水平可部分逆转这种抑制作用，这表明MβCD对病毒感染的抑制是通过去除细胞胆固醇介导的。然而，将细胞膜分离为DIMS和去垢剂可溶性膜组分表明，在进入细胞过程中，PVR和脊髓灰质炎病毒衣壳蛋白都不是定位在DIMS，而是定位在去垢剂可溶性膜组分，并且它们的定位不受MβCD处理的影响。我们进一步证明，MβCD处理在135S颗粒形成后抑制RNA的递送。这些数据表明，细胞的胆固醇状态在基因组递送过程中很重要，并且这些进入途径与那些需要DIMS完整性的途径不同。
Upon binding to the poliovirus receptor (PVR), the poliovirus 160S particles undergo a conformational transition to generate 135S particles, which are believed to be intermediates in the virus entry process. The 135S particles interact with host cell membranes through exposure of the N termini of VP1 and the myristylated VP4 protein, and successful cytoplasmic delivery of the genomic RNA requires the interaction of these domains with cellular membranes whose identity is unknown. Because detergent-insoluble microdomains (DIMS) in the plasma membrane have been shown to be important in the entry of other picornaviruses, it was of interest to determine if poliovirus similarly required DIMS during virus entry. We show here that methyl(3-cyclodextrin (MbetaCD), which disrupts DIMS by depleting cells of cholesterol, inhibits virus infection and that this inhibition was partially reversed by partially restoring cholesterol levels in cells, suggesting that MbetaCD inhibition of virus infection was mediated by removal of cellular cholesterol. However, fractionation of cellular membranes into DIMS and detergent-soluble membrane fractions showed that both PVR and poliovirus capsid proteins localize not to DIMS but to detergent-soluble membrane fractions during entry into the cells, and their localization was unaffected by treatment with MbetaCD. We further demonstrate that treatment with MbetaCD inhibits RNA delivery after formation of the 135S particles. These data indicate that the cholesterol status of the cell is important during the process of genome delivery and that these entry pathways are distinct from those requiring DIM integrity.