Construction and characterization of recombinant senecavirus A expressing secreted luciferase for antiviral screening.

Senecavirus A (SVA) is a newly identified picornavirus associated with swine vesicular disease and neonatal mortality. The development of an SVA incorporating an exogenous reporter gene provides a powerful tool for viral research. In this study, we successfully constructed a recombinant SVA expressing Gaussia Luciferase (Gluc), termed rSVA-Gluc. The growth kinetics of rSVA-Gluc in BHK-21 cells were found to be comparable to those of the parental virus, and Gluc activity paralleled the virus growth curve. Genetic analysis revealed stable inheritance of the inserted reporter protein genes for at least six generations. We evaluated the utility of rSVA-Gluc in antiviral drug screening, and the results highlighted its potential as an effective tool for such purposes against SVA. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are available on request from the corresponding author.

Construction and characterization of a full-length infectious clone of an emerging senecavirus A strain.

Senecavirus A (SVA) is an emerging virus that causes vesicular disease in pigs. Construction of a full-length SVA cDNA clone is crucial for understanding its replication and pathogenesis. Here, we successfully constructed a CMV-promoter-driven infectious cDNA clone of the SVA isolate SVA/GX/CH/2018, which we named rSVA GX01. Sequence comparison between the pSVA GX01 and the parental isolate (SVA/GX/CH/2018) revealed three single-nucleotide differences. Four-week-old piglets were experimentally infected with either the parental virus or the cloned virus. The results showed that the cloned rSVA GX01 displayed weak pathogenicity in 4-week-old pigs compared to the parental virus SVA CH-GX-01-2018. The infectious clone of SVA will serve as a valuable tool for studying the viral replication cycle and for functional analysis of the viral genome.

Development of a recombinant reporter Getah virus for antiviral drug screening assays.

Getah virus (GETV), is an often neglected and re-emerging mosquito-borne RNA virus. GETV can cause illness accompanied with high fever, rash, incapacitating arthralgia and chronic arthritis or encephalitic disease in affected animals. Currently, there is no specific treatment or vaccine against GETV infection. In this study, we developed three recombinant viruses by inserting different reporter protein genes between the Cap and pE2 genes. The reporter viruses exhibited high replication capacity similar to the parental virus. The rGECiLOV and rGECGFP viruses were genetically stable within at least ten rounds of passages in BHK-21 cells. We confirmed that the reporter virus, rGECGFP, facilitated the antiviral assays against GETV by testing it with the known inhibitor, ribavirin. It was also found that the compound, doxycycline, showed an inhibitory effect on GETV replication. In addition, rGECGFP was found to be an authentic mimic of the parental virus infection in 3-day-old mice, but with milder pathogenicity. The reporter viruses will contribute to the assessment of viral replication and proliferation, tracking and elucidating of alphavirus-host interactions. In addition, they will help in the screening of potential antiviral compounds.

Spontaneous nanoinjection with carbon nanotubes: a molecular dynamics simulation study.

Based on the interactions between the zinc finger protein (ZNF) and single-walled carbon nanotubes (SWCNTs), we design a nanodevice for injecting ZNF spontaneously. The new injection device involves four essential components: a small-diameter SWCNT as a plunger, a large-diameter SWCNT as a tube as well as the nozzle and needle, ZNF and water solution. The injection behavior is demonstrated and analyzed using molecular dynamics simulations. The effects of the diameter, chirality and length of SWCNTs on the injection behavior are analyzed with the center of mass distance, the van der Waals interaction between ZNF and SWCNTs, the root-mean-square deviation of ZNF, and the radius of gyration for ZNF.