Kaplan G, Freistadt M S, Racaniello V R
Department of Microbiology, College of Physicians and Surgeons, Columbia University, New York, New York 10032.
J Virol. 1990 Oct;64(10):4697-702. doi: 10.1128/JVI.64.10.4697-4702.1990.
To examine the interaction of the poliovirus receptor (PVR) with virus and the role of the PVR in virus entry, the PVR was expressed in insect cells. Poliovirus bound to insect cells infected with a recombinant baculovirus (AcPVR) carrying cDNA encoding the PVR. Antibodies raised against PVR expressed in bacteria immunoprecipitated a 67-kilodalton polypeptide from cytoplasmic extracts of AcPVR-infected cells. Treatment of AcPVR-infected cells with tunicamycin revealed that the PVR is a glycoprotein containing N-glycosidic linkages and that carbohydrate accounts for nearly 50% of its molecular weight as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When PVR was solubilized from AcPVR-infected insect cells and incubated with poliovirus, viral infectivity was neutralized. Sedimentation analysis revealed that irreversibly altered 135S particles were formed after incubation of poliovirus at 37 degrees C with solubilized extracts of AcPVR-infected insect cells. These results demonstrate that poliovirus eclipse may result from interaction with the cell receptor at neutral pH in the absence of membranes and suggest that soluble receptors may be effective antiviral agents against picornaviruses.
为研究脊髓灰质炎病毒受体（PVR）与病毒的相互作用以及PVR在病毒进入过程中的作用，PVR在昆虫细胞中表达。脊髓灰质炎病毒与感染了携带编码PVR的cDNA的重组杆状病毒（AcPVR）的昆虫细胞结合。针对在细菌中表达的PVR产生的抗体从AcPVR感染细胞的细胞质提取物中免疫沉淀出一条67千道尔顿的多肽。用衣霉素处理AcPVR感染的细胞表明，PVR是一种含有N-糖苷键的糖蛋白，通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳估计，碳水化合物占其分子量的近50%。当从AcPVR感染的昆虫细胞中溶解PVR并与脊髓灰质炎病毒一起孵育时，病毒感染性被中和。沉降分析显示，脊髓灰质炎病毒在37℃下与AcPVR感染的昆虫细胞的溶解提取物孵育后形成了不可逆改变的135S颗粒。这些结果表明，脊髓灰质炎病毒的隐蔽期可能是由于在无膜情况下在中性pH值下与细胞受体相互作用所致，并提示可溶性受体可能是抗微小核糖核酸病毒的有效抗病毒剂。
