草鱼呼肠孤病毒（Grass carp reovirus, GCRV）是草鱼出血病的致病病原。我们已证实GCRV外衣壳骨架蛋白VP5诱导产生的中和抗体可以抑制病毒侵染，这一结果表明VP5可能与宿主细胞表面受体相互作用介导病毒入侵。通过构建草鱼肾细胞的cDNA酵母双杂交文库及杂交阳性菌落的测序分析，我们发现草鱼 层粘连蛋白受体（Laminin receptor, LR）与GCRV病毒的VP5蛋白可以在酵母内相互作用。本项目计划利用病毒覆盖蛋白结合法、LR-VP5体外结合抑制试验、受体阻断剂竞争抑制实验等多种方法进一步确证该受体与GCRV病毒的相互作用。在此基础上运用共聚焦显微镜等技术在早晚期内吞体中研究VP5和LR的共定位，并阐明受体介导的内吞作用是否病毒吸附受体后进入细胞的主要途径。本研究首次鉴定和分析草鱼呼肠孤病毒的细胞受体，对了解病毒感染机制和开发抗病毒药物具有重要意义。

Grass carp reovirus (GCRV) is the causing pathogen of grass carp hemorrhagic disease. We have identified that outercapsid VP5 protein of GCRV was necessary for viral entrance into host cells by in vitro microneutralization assay, which suggests the potential role of VP5 in mediating viral entry.This study sought to isolate and characterize the receptor protein used by GCRV to gain entry into grass carp kidney cells (CIK cell). The Laminin receptor (LR) was identified as the interacting partner for outer capsid protein VP5 of GCRV by using the yeast two-hybrid technology in Saccharomyces cerevisiae. Here, we plan to further characterize LR-VP5 interaction by virus overlay protein binding assay (VOPBA), infection inhibition assay and protein binding inhibition assay. To further characterize receptor-mediated endocytosis, localization of LR and VP5 will be investigated in early, late, and recycling endosomes during virus entry into host cells by Confocal microscopy, as well as the effect of disfunctional endosome on viral entry. The results will enhance the understanding of infection mechanism of aquareovirus and pave the way for the development of antiviral drug to complement the classical vaccination approach.