Research progress in NSP2 of porcine reproductive and respiratory syndrome virus.

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) Nonstructural Protein 2 (NSP2), a multifunctional protein encoded by a highly variable gene, plays pivotal roles in viral pathogenesis. This review synthesizes current progress on NSP2 genetic variations, including mutations, deletions, and interstrain recombination-with emphasis on its hypervariable regions. NSP2 interactions with viral proteins and its truncated isoform (NSP2TF) are analyzed in the context of viral assembly and budding. Concurrently, NSP2 binds host proteins to manipulate host pathways, thereby facilitating viral replication, autophagy, tropism, and immune evasion through interferon suppression and cytokine modulation. The potential of NSP2 as a marker vaccine candidate and diagnostic target is evaluated, demonstrating its applicability in developing novel PRRSV NSP2 control strategies. This comprehensive analysis advances the understanding of PRRSV pathogenesis and provides a foundation for future vaccine development.