title: Variable interference with interferon signal transduction by different strains of porcine reproductive and respiratory syndrome virus.
abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) is a positive-sense single-strand RNA virus that has contributed to substantial losses to the swine industry. The objective of this study was to examine the interference of interferon (IFN)-activated signaling by PRRSV viral proteins and compare the effects of several PRRSV strains on the IFN signaling. Three non-structural proteins (nsp 1β, 7 and 12) and two structural proteins (GP3 and N) of VR-2385 were found to significantly inhibit the expression of IFN-stimulated response element (ISRE) luciferase reporter. Nsp1β and N showed robust inhibition and their-encoding sequences from the six PRRSV strains (VR-2385, Ingelvac PRRS MLV, VR-2332, NVSL97-7895, MN184, and Lelystad) were cloned for further characterization. The nsp1βs of all the strains except MLV inhibited expression of IFN-induced ISRE reporter, interferon-stimulated gene 56 (ISG56) and signal transducer and activator of transcription 2 (STAT2). The N proteins inhibited the IFN-induced ISRE reporter expression and STAT2 elevation and blocked nuclear translocation of STAT1. In MARC-145 cells, all the six PRRSV strains with the exception of MN184 blocked the activity of exogenous IFN-α. In primary porcine pulmonary alveolar macrophages (PAMs), only MLV and NVSL failed to inhibit the activity of IFN-α. These results indicate that some PRRSV strains, such as NVSL and MN184, have variable effects on IFN-activated signaling in the two types of cells.
authors: College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China.
authors: Rong
authors: R
authors: Wang
authors: Yuchen
authors: Y
authors: Nan
authors: Ying
authors: Y
authors: Yu
authors: Zengqi
authors: Z
authors: Yang
authors: Yan-Jin
authors: YJ
authors: Zhang
mesh_terms: D000818:Animals; D002460:Cell Line; D006801:Humans; D007372:Interferons / Q000494:pharmacology*; D016676:Macrophages, Alveolar / Q000276:immunology / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus / Q000145:classification / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D015398:Signal Transduction; D013552:Swine; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology
chemical_list: D014764:Viral Proteins; D007372:Interferons
keywords: Interferon (IFN) signaling; JAK/STAT signal pathway; N; Nsp1β; Porcine reproductive and respiratory syndrome virus (PRRSV)