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Porcine parvovirus nonstructural protein NS1 activates NF-?B and it involves TLR2 signaling pathway.

ABSTRACT: BACKGROUND:Porcine parvovirus (PPV) is a single-stranded DNA virus that causes porcine reproductive failure. It is of critical importance to study PPV pathogenesis for the prevention and control of the disease. NS1, a PPV non-structural protein, is participated in viral DNA replication, transcriptional regulation, and cytotoxicity. Our previous research showed that PPV can activate nuclear factor kappa B (NF-?B) signaling pathway and then up-regulate the expression of interleukin (IL)-6. OBJECTIVES:Herein, the purpose of this study is to determine whether the non-structural protein NS1 of PPV also has the same function. METHODS:Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay, western blot, immunofluorescence assay and small interfering RNA (siRNA) were used. RESULTS:Our findings demonstrated that PPV NS1 protein can up-regulate the expression levels of IL-6 and tumor necrosis factor-alpha in a dose-dependent manner. Moreover, PPV NS1 protein was found to induce the phosphorylation of I?B?, then leading to the phosphorylation and nuclear translocation of NF-?B. In addition, the NS1 protein activated the upstream pathways of NF-?B. Meanwhile, TLR2-siRNA assay showed TLR2 plays an important role in the activation of NF-?B signaling pathway induced by PPV-NS1. CONCLUSIONS:These findings indicated that PPV NS1 protein induced the up-regulated of IL-6 expression through activating the TLR2 and NF-?B signaling pathways. In conclusion, these findings provide a new avenue to study the innate immune mechanism of PPV infection.

SUBMITTER: Jin X

PROVIDER: S-EPMC7263913 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Porcine parvovirus nonstructural protein NS1 activates NF-κB and it involves TLR2 signaling pathway.

Jin Xiaohui X Yuan Yixin Y Zhang Chi C Zhou Yong Y Song Yue Y Wei Zhanyong Z Zhang Gaiping G

Journal of veterinary science 20200501 3

<h4>Background</h4>Porcine parvovirus (PPV) is a single-stranded DNA virus that causes porcine reproductive failure. It is of critical importance to study PPV pathogenesis for the prevention and control of the disease. NS1, a PPV non-structural protein, is participated in viral DNA replication, transcriptional regulation, and cytotoxicity. Our previous research showed that PPV can activate nuclear factor kappa B (NF-κB) signaling pathway and then up-regulate the expression of interleukin (IL)-6. ...[more]

PMID: 32476323

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Porcine parvovirus nonstructural protein NS1 activates NF-?B and it involves TLR2 signaling pathway.

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Porcine parvovirus nonstructural protein NS1 activates NF-κB and it involves TLR2 signaling pathway.

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