Chen Jianing, He Wen-Rui, Shen Liang, Dong Hong, Yu Jiahui, Wang Xiao, Yu Shaoxiong, Li Yongfeng, Li Su, Luo Yuzi, Sun Yuan, Qiu Hua-Ji
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
J Virol. 2015 May;89(9):4894-906. doi: 10.1128/JVI.00019-15. Epub 2015 Feb 18.
Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), a highly contagious, economically important viral disease in many countries. The E(rns) and E2 envelope glycoproteins are responsible for the binding to and entry into the host cell by CSFV. To date, only one cellular receptor, heparan sulfate (HS), has been identified as being involved in CSFV attachment. HS is also present on the surface of various cells that are nonpermissive to CSFV. Hence, there must be another receptor(s) that has been unidentified to date. In this study, we used a set of small interfering RNAs (siRNAs) against a number of porcine cell membrane protein genes to screen cellular proteins involved in CSFV infection. This approach resulted in the identification of several proteins, and of these, the laminin receptor (LamR) has been demonstrated to be a cellular receptor for several viruses. Confocal analysis showed that LamR is colocalized with CSFV virions on the membrane, and a coimmunoprecipitation assay indicated that LamR interacts with the CSFV E(rns) protein. In inhibition assays, anti-LamR antibodies, soluble laminin, or LamR protein significantly inhibited CSFV infection in a dose-dependent manner. Transduction of PK-15 cells with a recombinant lentivirus expressing LamR yielded higher viral titers. Moreover, an attachment assay demonstrated that LamR functions during virus attachment. We also demonstrate that LamR acts as an alternative attachment receptor, especially in SK6 cells. These results indicate that LamR is a cellular attachment receptor for CSFV.
Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), an economically important viral disease affecting the pig industry in many countries. To date, only heparan sulfate (HS) has been identified to be an attachment receptor for CSFV. Here, using RNA interference screening with small interfering RNAs (siRNAs) against a number of porcine membrane protein genes, we identified the laminin receptor (LamR) to be another attachment receptor. We demonstrate the involvement of LamR together with HS in virus attachment, and we elucidate the relationship between LamR and HS. LamR also serves as an attachment receptor for many viral pathogens, including dengue virus, a fatal human flavivirus. The study will help to enhance our understanding of the life cycle of flaviviruses and the development of antiviral strategies for flaviviruses.
经典猪瘟病毒（CSFV）是经典猪瘟（CSF）的病原体，CSF是一种在许多国家具有高度传染性、经济上很重要的病毒性疾病。E(rns)和E2包膜糖蛋白负责CSFV与宿主细胞的结合和进入。迄今为止，仅一种细胞受体硫酸乙酰肝素（HS）被确定参与CSFV的附着。HS也存在于对CSFV不敏感的各种细胞表面。因此，必定存在另一种迄今尚未被鉴定的受体。在本研究中，我们使用了一组针对多个猪细胞膜蛋白基因的小干扰RNA（siRNA）来筛选参与CSFV感染的细胞蛋白。这种方法鉴定出了几种蛋白，其中层粘连蛋白受体（LamR）已被证明是几种病毒的细胞受体。共聚焦分析表明，LamR在细胞膜上与CSFV病毒粒子共定位，免疫共沉淀试验表明LamR与CSFV E(rns)蛋白相互作用。在抑制试验中，抗LamR抗体、可溶性层粘连蛋白或LamR蛋白以剂量依赖的方式显著抑制CSFV感染。用表达LamR的重组慢病毒转导PK-15细胞产生了更高的病毒滴度。此外，附着试验表明LamR在病毒附着过程中起作用。我们还证明LamR作为一种替代附着受体，尤其是在SK6细胞中。这些结果表明LamR是CSFV的细胞附着受体。
经典猪瘟病毒（CSFV）是经典猪瘟（CSF）的病原体，CSF是一种影响许多国家养猪业的重要病毒性疾病。迄今为止，仅硫酸乙酰肝素（HS）被确定为CSFV的附着受体。在此，我们使用针对多个猪膜蛋白基因的小干扰RNA（siRNA）进行RNA干扰筛选，鉴定出层粘连蛋白受体（LamR）是另一种附着受体。我们证明了LamR与HS共同参与病毒附着，并阐明了LamR与HS之间的关系。LamR也是许多病毒病原体的附着受体，包括致命的人类黄病毒登革病毒。该研究将有助于增强我们对黄病毒生命周期的理解以及黄病毒抗病毒策略的开发。
