College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China.
School of Animal Husbandry and Medical Engineering, Xinyang Agriculture and Forestry University, Xinyang 464000, China.
Vet Microbiol. 2020 Aug;247:108793. doi: 10.1016/j.vetmic.2020.108793. Epub 2020 Jul 13.
Porcine epidemic diarrhea virus (PEDV) belongs to the Alphacoronavirus genus in the Coronaviridae family. Similar to other coronaviruses, PEDV encodes two papain-like proteases. Papain-like protease (PLP)2 has been proposed to play a key role in antagonizing host innate immunity. However, the function of PLP1 remains unclear. In this study, we found that overexpression of PLP1 significantly promoted PEDV replication and inhibited production of interferon-β. Immunoprecipitation and mass spectrometry were used to identify cellular interaction partners of PLP1. Host cell poly(C) binding protein 2 (PCBP2) was determined to bind and interact with PLP1. Both endogenous and overexpressed PCBP2 co-localized with PLP1 in the cytoplasm. Overexpression of PLP1 upregulated expression of PCBP2. Furthermore, overexpression of PCBP2 promoted PEDV replication. Silencing of endogenous PCBP2 using small interfering RNAs attenuated PEDV replication. Taken together, these data demonstrated that PLP1 negatively regulated the production of type 1 interferon by interacting with PCBP2 and promoted PEDV replication.
猪流行性腹泻病毒（PEDV）属于冠状病毒科冠状病毒属的α冠状病毒。与其他冠状病毒类似，PEDV 编码两种木瓜样蛋白酶。木瓜样蛋白酶 2（PLP2）被认为在拮抗宿主固有免疫中发挥关键作用。然而，PLP1 的功能尚不清楚。在本研究中，我们发现 PLP1 的过表达显著促进了 PEDV 的复制，并抑制了干扰素-β的产生。免疫沉淀和质谱分析用于鉴定 PLP1 的细胞相互作用伙伴。发现宿主细胞多聚（C）结合蛋白 2（PCBP2）与 PLP1 结合并相互作用。内源性和过表达的 PCBP2 均与 PLP1 在细胞质中共定位。PLP1 的过表达上调了 PCBP2 的表达。此外，PCBP2 的过表达促进了 PEDV 的复制。用小干扰 RNA 沉默内源性 PCBP2 可减弱 PEDV 的复制。总之，这些数据表明 PLP1 通过与 PCBP2 相互作用负调控 I 型干扰素的产生，并促进 PEDV 的复制。
