The evolutionary and structural characteristics of the GP5 gene were analyzed to predict potential evolutionary patterns of PRRSV and provide molecular insights into prevention strategies and vaccine development.
Abstract
Simple Summary Porcine reproductive and respiratory virus (PRRSV) causes significant economic losses in the German swine industry. Yet data on its main structural protein, GP5, have not been systematically analyzed in Germany. GP5 is a glycosylated envelope protein, which plays an important role in immune evasion. In the present study, the evolutionary and structural characteristics of the GP5 gene were analyzed to predict potential evolutionary patterns of PRRSV. The analysis provides molecular insights into prevention strategies and vaccine development. Additional studies on whole genome analysis and spatial structure analysis are needed to deepen the understanding of German PRRSV evolution and the structure of GP5, which can facilitate vaccine development and lay the foundation for prevention strategies.
Bovine coronavirus (BCoV) is a key pathogen causing calf diarrhea and bovine respiratory diseases, bringing sustained economic losses to the cattle industry. As an RNA virus, BCoV possesses high mutation and recombination capacities, leading to prominent genomic genetic diversity. The genome contains hypervariable and conserved regions, with the S (especially S1), HE and Open Reading Frame (ORF4) genes serving as major variation hotspots linked to viral antigenicity, tissue tropism shift and immune evasion. Host immune pressure drives strong positive selection on S protein antigenic variation. This review discusses existing research limitations and proposes future directions including genomic surveillance, reverse genetics verification and broad-spectrum vaccine development to support BCoV prevention and control.
Dong Wang, Wen-Zheng Zhang, Zheng Nie et al.· Viruses· 0 citations
Background/Objectives: Porcine reproductive and respiratory syndrome virus type 2 (PRRSV-2) remains the predominant genotype circulating in China and continues to evolve through mutation and recombination. Although NSP1 is recognized as a multifunctional nonstructural protein involved in immune regulation, its genetic variation among PRRSV-2 strains circulating in China has not been comprehensively characterized. Methods: In this study, 425 complete NSP1 sequences, primarily representing PRRSV-2 strains circulating in China, were analyzed, and 48 representative strains were selected for pairwise percent-identity visualization. Results: Pairwise nucleotide identity among the 48 representative strains was found to range from 80.1% to 100.0%, with the lowest value detected between AHBZ and SD-R, whereas pairwise amino-acid identity ranged from 79.6% to 100.0%, with the lowest value detected between AHBZ and HNhx. Among the 425 aligned amino-acid sequences, 290 variable sites and 93 completely conserved sites were identified. The broad-lineage distribution was composed of Lineage 1 (n = 79), Lineage 3 (n = 4), Lineage 5 (n = 21), and Lineage 8 (n = 321). A global FEL dN/dS of approximately 0.2979 was estimated from 379 non-recombinant unique haplotypes, and seven high-confidence candidate positively selected sites—42, 239, 255, 302, 367, 370, and 378—were supported by MEME, FEL, and FUBAR. A descriptive lineage-biased pattern concentrated in Lineage 5 was observed for NSP1β Val19Ile, corresponding to full-length NSP1 V199I. Eight candidate recombination events were identified using RDP4, and six representative events were further examined using SimPlot. Conclusions: Overall, NSP1 was found to be under predominant purifying selection while retaining localized variability, lineage-biased residue patterns, and candidate recombination signals that should be interpreted cautiously and validated experimentally.
Tian-Yuan Nie, Jiaman Li, Si-Qi Ye et al.· Genes· 0 citations
This research presents a comprehensive analysis of the genetic landscape of prevalent NDV strains in Bangladesh between 2010 and 2024 using full‐length coding sequences of the fusion (F) gene and unraveled considerable genetic divergence.
Farah Zereen, Md. Abdur Rahman, M. Hossain et al.· Veterinary Medicine Internat...· 0 citations
Porcine epidemic diarrhea virus (PEDV) G2c variants have recently emerged, posing significant challenges to swine health management. As a major coronavirus affecting the swine industry, PEDV exhibits extensive genetic variability, which has greatly complicated disease control. Current vaccines provide suboptimal protection under field conditions. Therefore, the isolation of recently circulating strains and the establishment of a robust reverse genetics system are critical for advancing the study of emerging variants and facilitating rational vaccine development. In this study, a PEDV field strain designated PEDV-BJ-2023 was isolated from diarrheic piglets in Guizhou, China. Phylogenetic analysis based on the complete genome and spike gene classified PEDV-BJ-2023 within the emerging G2c lineage. To facilitate functional studies, a full-length infectious cDNA clone was constructed using transformation-associated recombination cloning in yeast. Furthermore, an enhanced green fluorescent protein reporter virus was generated via CRISPR/Cas9-assisted homologous recombination by inserting an EGFP-2A cassette upstream of the nucleocapsid gene. The recombinant viruses displayed virion morphology and plaque characteristics similar to those of the parental wild-type PEDV-BJ-2023 strain, although the parental virus exhibited faster replication during the early stage of infection in vitro. In 5-day-old piglets, all three viruses caused severe diarrhea, weight loss, and intestinal lesions; however, recombinant viruses exhibited slightly reduced viral shedding and pathogenicity, with rPEDV-EGFP being the most attenuated. Notably, rPEDV-EGFP maintained stable EGFP expression over eight serial passages. This study establishes a reverse genetics platform for an emerging G2c PEDV strain and provides a stable fluorescent reporter virus, offering valuable tools for visualizing viral infection and investigating virus–host interactions.
Fan Zhang, He-Lu Liu, Linlong Ji et al.· Viruses· 0 citations
ABSTRACT Porcine reproductive and respiratory syndrome virus (PRRSV) remains a major threat to the swine industry globally. In China, the dominance of PRRSV 2 is complicated by the emergence and co-circulation of genetically distinct strains, including a rising number of PRRSV 1 cases. In this study, the concurrent circulation of PRRSV 1 and PRRSV 2 was identified, and two novel strains AHB1 and Chah2022 were isolated from a single sow farm experiencing reproductive failure. Genetic analysis revealed that AHB1 shared 81.6%-83.6% nucleotide identity with subtype 1 strains of PRRSV 1 and clustered within a new evolutionary branch, characterized by a continuous 54-amino acid deletion in nsp2 and 1-amino acid deletion in the GP3-GP4 overlap region. In contrast, Chah2022 was identified as a recombinant virus with NADC30-like (lineage 1) and highly pathogenic PRRSV-like (lineage 8) strains. Pathogenicity assessment in nursery piglet model demonstrated that both AHB1 and Chah2022 had established systemic and persistent infections, although with low or moderate clinical signs. Our findings provide the evidence of PRRSV 1 and PRRSV 2 concurrent circulation in the single sow farm in China, which highlights the ongoing evolution of both Chinese PRRSV species and underscores the urgent need for enhanced surveillance and updated control strategies.
Zhendong Zhang, Di Gao, Zihe Wang et al.· Virulence· 0 citations
It is demonstrated that the attenuated strain AHFY‐F140 represents a promising vaccine candidate against both NADC30‐like and JXA1‐like PRRSV infections.
Hengjiao Zhang, Jiakai Zhao, Chengxin Zhang et al.· Transboundary and Emerging D...· 0 citations
