Direct Interaction Between CD163 N-Terminal Domain and MYH9 C-Terminal Domain Contributes to Porcine Reproductive and Respiratory Syndrome Virus Internalization by Permissive Cells
Direct Interaction Between CD163 N-Terminal Domain and MYH9 C-Terminal Domain Contributes to Porcine Reproductive and Respiratory Syndrome Virus Internalization by Permissive Cells
复制标题
CD163 N 端结构域和 MYH9 C 端结构域之间的直接相互作用有助于允许细胞内化猪繁殖与呼吸综合征病毒
DOI：
10.3389/fmicb.2019.01815
复制
发表时间：
2019-08-06
影响因子：
5.2
通讯作者：
Zhou, En-Min
中科院分区：
文献类型：
--
作者：
Hou, Gaopeng;Xue, Biyun;Zhou, En-Min
猪繁殖与呼吸综合征病毒（PRRSV）对单核细胞-巨噬细胞谱系的细胞具有高度限制的嗜性，包括猪肺泡巨噬细胞（PAM）。PRRSV进入允许细胞涉及除了两个必需的宿主细胞受体CD 163和MYH 9之外的几种介质。目前尚不清楚CD 163是否直接与MYH 9相互作用和/或协同作用以促进PRRSV感染。在这项研究中，CD 163和MYH 9从PAM中共免疫沉淀，而不考虑PRRSV感染状态。进一步的截短分析表明，含有清道夫受体富含半胱氨酸的结构域1至4（SRCR 1 -4）的CD 163 N-末端区域直接与MYH 9 C-末端结构域区域相互作用，而不涉及其他衔接蛋白。同时，稳定表达截短的猪CD 163 SRCR 1 -4结构域的非允许性HEK 293 T细胞不支持病毒附着。然而，病毒附着于稳定表达SRCR 5-CT结构域的细胞被证明在没有明显的病毒内化的情况下发生。SRCR 1 -4结构域参与病毒内化的事实进一步证明，重组SRCR 1 -4蛋白与PAM孵育消除了随后的病毒内化的许可细胞。这些结果表明，CD 163 SRCR 1 -4与MYH 9 C-末端结构域相互作用，以促进PRRSV病毒粒子在允许细胞中的内化，从而扩大了我们对PRRSV细胞侵袭机制的理解。
Porcine reproductive and respiratory syndrome virus (PRRSV) has a highly restricted tropism for cells of the monocyte-macrophage lineage, including porcine alveolar macrophages (PAMs). PRRSV entry into permissive cells involves several mediators in addition to two required host cell receptors, CD163 and MYH9. It is unknown whether CD163 directly interacts and/or cooperates with MYH9 to facilitate PRRSV infection. In this study, CD163 and MYH9 were co-immunoprecipitated from PAMs regardless of PRRSV infection status. Further truncation analysis indicated that the CD163 N-terminal region, containing scavenger receptor cysteine-rich domains 1 to 4 (SRCR1-4), directly interacts with the MYH9 C-terminal domain region without involvement of other adaptor proteins. Meanwhile, non-permissive HEK293T cells that stably expressed truncated swine CD163 SRCR1-4 domain did not support virus attachment. However, virus attachment to cells stably expressing SRCR5-CT domain was demonstrated to occur without appreciable virus internalization. The involvement of the SRCR1-4 domain in virus internalization was further demonstrated by the fact that incubation of recombinant SRCR1-4 protein with PAMs abolished subsequent virus internalization by permissive cells. These results demonstrated that CD163 SRCR1-4 interacts with the MYH9 C–terminal domain to facilitate PRRSV virion internalization in permissive cells, thus expanding our understanding of PRRSV cell-invasion mechanisms.