The VP3 protein of duck hepatitis A virus mediates host cell adsorption and apoptosis.
Yalan LaiNi ZengMingshu WangAn-Chun ChengQiao YangYing WuRenyong JiaDekang ZhuXinXin ZhaoShun ChenMafeng LiuShaqiu ZhangYin WangZhiwen XuZhengli ChenLing ZhuQihui LuoYunya LiuYanling YuLing ZhangJuan HuangBin TianLeichang PanMujeeb Ur RehmanXiaoyue ChenPublished in: Scientific reports (2019)
Duck hepatitis A virus (DHAV) causes an infectious disease that mainly affects 1- to 4-week-old ducklings, resulting in considerable loss to the duck industry. Although there have been many studies on DHAV in recent years, the effects on host infection and pathogenesis of DHAV-1 remain largely unknown. This study investigated the effects of the DHAV-1 structural protein VP3 on DHAV-1 virus adsorption and apoptosis to explore the role of VP3 in the viral life cycle. The effects of DHAV-1 VP3 and an antibody against the protein on virion adsorption was analyzed by qRT-PCR. The results showed that the virus copy number for the rabbit anti-VP3 IgG-treated group was significantly lower than that for the negative control group but higher than that for the rabbit anti-DHAV-1 IgG-treated group. This result indicates that VP3 mediates DHAV-1 virus adsorption but that it is not the only protein that involved in this process. In addition, a eukaryotic recombinant plasmid, pCAGGS/VP3, was transfected into duck embryo fibroblasts (DEFs), and the apoptotic rate was determined by DAPI staining, the TUNEL assay and flow cytometry. DAPI staining showed nucleus fragmentation and nuclear edge shifting. TUNEL assay results revealed yellow nuclei, and flow cytometry indicated a significant increase in the apoptotic rate. In addition, qRT-PCR revealed increased in the transcriptional levels of the apoptotic caspase-3, -8 and -9, with the largest increase for caspase-3, followed by caspase-9 and caspase-8. Enzyme activity analysis confirmed these results. Furthermore, the VP3 protein decreased the mitochondrial membrane potential, and the transcriptional levels of the proapoptotic factors Bak, Cyt c and Apaf-1 in the mitochondrial apoptotic pathway were significantly upregulated. These data suggest that expression of VP3 in DEFs induces apoptosis and may primarily activate caspase-3-induced apoptosis through mitochondrion-mediated intrinsic pathways. The findings provide scientific data to clarify DHAV-1 infection and pathogenesis.
Keyphrases
- disease virus
- cell death
- induced apoptosis
- flow cytometry
- endoplasmic reticulum stress
- oxidative stress
- cell cycle arrest
- copy number
- protein protein
- signaling pathway
- binding protein
- gene expression
- single cell
- amino acid
- clinical trial
- big data
- high throughput
- poor prognosis
- transcription factor
- dna methylation
- bone marrow
- risk assessment
- randomized controlled trial
- aqueous solution
- mesenchymal stem cells
- climate change
- single molecule
- cell therapy
- human health
- high resolution
- pi k akt
- high speed