State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China; Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China; Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China; Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing 100193, China; Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
Vet Microbiol. 2022 Jun;269:109434. doi: 10.1016/j.vetmic.2022.109434. Epub 2022 Apr 14.
Porcine reproductive and respiratory syndrome (PRRS) caused by PRRS virus (PRRSV) has been recognized as one of the severest epidemics in pigs worldwide. microRNAs (miRNAs) play important roles in a variety of biological processes, including cell differentiation, proliferation and death, as well as viral infections and antiviral immune responses. In this study, we found that miR-142-3p was expressed lower in cells susceptible to PRRSV infection than in cells less or no permissive to PRRSV infection. Subsequently, we showed that overexpression of miR-142-3p remarkably inhibited PRRSV infection in PAMs, while blockage of endogenous miR-142-3p significantly enhanced PRRSV replication. Then, we demonstrated that miR-142-3p directly targeted Ras-related C3 botulinum toxin substrate 1 (Rac1), a member of Rho GTPases family, by using luciferase reporter assay and UV cross-linking and immunoprecipitation (CLIP) assay. Importantly, we verified that miR-142-3p inhibited PRRSV entry into PAMs and accordingly suppressed PRRSV infection by downregulating Rac1 expression. These findings reveal an important role of miR-142-3p in modulating PRRSV infection and provide us with some ideas for developing novel antiviral therapy against PRRSV infection.
猪繁殖与呼吸综合征（PRRS）由猪繁殖与呼吸综合征病毒（PRRSV）引起，已被认为是全球范围内最严重的猪病之一。microRNAs（miRNAs）在多种生物学过程中发挥重要作用，包括细胞分化、增殖和死亡，以及病毒感染和抗病毒免疫反应。在本研究中，我们发现，与对 PRRSV 感染较不敏感或不敏感的细胞相比，易感 PRRSV 感染的细胞中 miR-142-3p 的表达水平较低。随后，我们表明，miR-142-3p 的过表达可显著抑制 PAMs 中的 PRRSV 感染，而内源性 miR-142-3p 的阻断则显著增强了 PRRSV 的复制。然后，我们通过荧光素酶报告基因检测、UV 交联和免疫沉淀（CLIP）实验证实 miR-142-3p 可直接靶向 Ras 相关 C3 肉毒杆菌毒素底物 1（Rac1），Rac1 是 Rho GTPases 家族的成员。重要的是，我们验证了 miR-142-3p 通过下调 Rac1 表达来抑制 PRRSV 进入 PAMs，从而抑制 PRRSV 感染。这些发现揭示了 miR-142-3p 在调节 PRRSV 感染中的重要作用，并为我们开发针对 PRRSV 感染的新型抗病毒治疗提供了一些思路。
