Publications by authors named "LeiChang Pan"

Duck plague virus (DPV) is a high-morbidity fowl alphaherpesvirus that causes septicemic lesions in various organs. Most DPV genes are conserved among herpesviruses, while a few are specific to fowl herpesviruses, including the gene, for which there is currently no literature describing its biological properties and functions. This study first addressed whether the LORF3 protein is expressed by making specific polyclonal antibodies.

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DNAzymes effectively inhibit the expression of viral genes. Duck hepatitis A virus type-1 (DHAV-1) genomic RNA carries an internal ribosome entry site (IRES). The IRES initiates the translation of DHAV-1 a mechanism that differs from that of cap-dependent translation.

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Duck plague virus (DPV) belongs to the and causes high morbidity and mortality in waterfowl. UL47 is a large abundant structural protein in DPV, which means that UL47 protein plays an important role in virus replication. US3 protein, as a viral protein kinase in alphaherpesviruses, has been reported to be critical for DPV virion assembly.

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Duck plague caused by duck plague virus (DPV) is a highly contagious disease that can cause serious morbidity and death in waterfowl such as ducks and geese, and bring huge economic losses to the duck industry. In this study, on the basis of the duck plague virus gC gene deletion strain CHv-ΔgC, based on the duck plague virus bacterial artificial chromosome (BAC) platform in our laboratory, the gE gene was knocked out using the traceless deletion technology to obtain gC/gE double gene deletion candidate vaccine strain CHv-ΔgC/gE. The double gene deletion strain (CHv-ΔgC/gE) constructed in this study has greatly weakened virulence, no pathogenicity to ducks, and stable genetic characteristics and .

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Duck hepatitis A virus type 1 (DHAV-1) is one of the main pathogens responsible for death in ducklings. Autophagy is a catabolic process that maintains cellular homeostasis, and the PI3KC3 protein plays an important role in the initiation of autophagy. DHAV-1 infection induces autophagy in duck embryo fibroblasts (DEFs) but the molecular mechanism between it and autophagy has not been reported.

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Article Synopsis
  • Duck plague virus (DPV) severely affects ducks and geese, causing significant immunosuppression and challenges in understanding its infection mechanisms due to a lack of cell models.
  • A study compared gene expressions in duck monocyte/macrophage cells infected with virulent (CHv) and avirulent (CHa) strains of DPV, revealing thousands of differentially expressed genes involved in immune response and signaling pathways.
  • The findings indicate that DPV manipulation of the JNK pathway negatively affects the interferon signaling, potentially aiding viral replication, which could help in developing new prevention strategies against DPV infections.
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Gasdermin E (GSDME) is a member of the gasdermin family. Cleavage of mammalian GSDME by apoptotic caspases or granzyme proteases liberates the N-terminal effector domain (GSDME-N), which is capable of forming membrane pores and executing inflammation and cell death. Herein, duck GSDME was first cloned with a total length of 1500 bp and encoding 499 amino acids (aa), which is most evolutionally related to the chicken GSDME.

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  • The study explores how the duck Tembusu virus (DTMUV) uses its NS2A protein to inhibit the IFNβ signaling pathway by binding to STING, impacting TBK1 phosphorylation.
  • The research identifies specific amino acids in the NS2A protein that are crucial for this interaction and demonstrates that mutations at these sites can significantly impair viral replication and reduce virulence in infected ducks.
  • These findings suggest potential strategies for developing attenuated flaviviruses by targeting their immune evasion mechanisms.
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Duck plague virus (DPV) can cause high morbidity and mortality in many waterfowl species within the order Anseriformes. The DPV genome contains 78 open reading frames (ORFs), among which the LORF2, LORF3, LORF4, LORF5, and SORF3 genes are unique genes of avian herpesvirus. In this study, to investigate the role of this unique LORF5 gene in DPV proliferation, we generated a recombinant virus that lacks the LORF5 gene by a two-step red recombination system, which cloned the DPV Chinese virulent strain (DPV CHv) genome into a bacterial artificial chromosome (DPV CHv-BAC); the proliferation law of LORF5-deleted mutant virus on DEF cells and the effect of LORF5 gene on the life cycle stages of DPV compared with the parent strain were tested.

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The duck hepatitis A virus 1 (DHAV-1) 2C protein was predicted to be a superfamily III helicase member and includes nucleotide binding (NTB) and putative RNA helicase activity motifs. To study whether DHAV-1 2C protein has NTB activity, we expressed DHAV-1 2C protein with maltose binding protein (MBP) to solve its poor solubility in a prokaryotic expression system. We showed that the DHAV-1 2C protein has nucleoside triphosphatase (NTPase) activity by measuring the released phosphate.

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Duck hepatitis A virus (DHAV), which mainly infects 1- to 4-week-old ducklings, has a fatality rate of 95% and poses a huge economic threat to the duck industry. However, the mechanism by which DHAV-1 regulates the immune response of host cells is rarely reported. This study examined whether DHAV-1 contains a viral protein that can regulate the innate immunity of host cells and its specific regulatory mechanism, further exploring the mechanism by which DHAV-1 resists the host immune response.

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  • Scientists found a new type of virus called goose pegivirus (GPgV) that affects geese and is different from other known types of pegivirus.
  • They collected 49 sick geese from two places in China (Sichuan and Chongqing) to see if they had GPgV and other viruses.
  • Results showed that 44.9% of the geese tested positive for GPgV, marking a high infection rate and revealing that GPgV can infect geese along with other viruses.
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Our previous studies reported that duck Tembusu virus nonstructural protein 2A (NS2A) is a major inhibitor of the IFNβ signaling pathway through competitively binding to STING with TBK1, leading to a reduction in TBK1 phosphorylation. Duck TMUV NS2B3 could cleave and bind STING to subvert the IFNβ signaling pathway. Here, we found that overexpression of duck TMUV NS4B could compete with TBK1 in binding to STING, reducing TBK1 phosphorylation and inhibiting the IFNβ signaling pathway by using the Dual-Glo Luciferase Assay System and the NanoBiT protein-protein interaction (PPI) assay.

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  • Cosignal molecules help transmit signals between cells to regulate the immune response, either enhancing (costimulation) or inhibiting (cosuppression) it.
  • A study successfully cloned and reported the complete cDNA sequence of the duck CD40 gene, a costimulatory molecule, for the first time.
  • The findings indicate that the duck CD40 molecule is significant for antiviral immune responses, contributing to the understanding of the avian immune system.
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Duck hepatitis A virus type 1 (DHAV-1) is one of the most deadly pathogens that endanger the duck industry. Most viruses usually turn off host translation after infection to facilitate viral replication and translation. For the first time report to our knowledge, DHAV-1 can induce eIF2α phosphorylation and inhibit cellular translation in duck embryo fibroblasts (DEFs).

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Duck Tembusu virus (DTMUV) and duck plague virus (DPV) are typical DNA and RNA viruses of waterfowl, causing drastic economic losses to the duck farm industry in terms of high mortality and decreased egg production. These 2 viruses reappear from time to time because the available vaccines fail to provide complete immunity and no clinical antiviral drugs are available for them. In the present study, we evaluated the antiviral activity of SC75741 for DTMUV, DPV, and the model virus, vesicular stomatitis virus infection in duck cells.

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Fowl cholera caused by Pasteurella multocida exerts a massive economic burden on the poultry industry. Lipopolysaccharide (LPS) is essential for the growth of P. multocida genotype L1 strains in chickens and specific truncations to the full length LPS structure can attenuate bacterial virulence.

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  • Riemerella anatipestifer is a significant pathogen in poultry, particularly serotypes 1 and 2, which lead to serious health issues and high mortality rates.
  • The study utilized gas chromatography-mass spectrometry (GC-MS) to analyze the intracellular metabolites of two strains, RA-CH-1 and RA-CH-2, revealing a higher abundance of metabolites in RA-CH-2.
  • Findings included the identification of 24 potential biomarkers and the reconstruction of metabolic models, illustrating the feasibility of distinguishing these strains based on their metabolic profiles.
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Duck hepatitis A virus 1 (DHAV-1) is a highly prevalent pathogen within adult ducks causing acute as well as chronic hepatitis which closely emulates the progression of human hepatitis. However, the underlying mechanisms of DHAV-1 persistence and the pathogenesis of chronic liver disease are not well defined. The association between hematopoietic reservoirs of virus and persistent infection is increasingly concerning.

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Duck enteritis virus (DEV) multifunctional tegument protein UL13 is predicted to be a conserved herpesvirus protein kinase; however, little is known about its subcellular localization signal. In this study, through transfection of 2 predicted nuclear signals of DEV UL13 fused to enhanced green fluorescent protein, 2 bipartite nuclear localization signals (NLS) were identified. We found that ivermectin blocked the NLS-mediated nuclear import of DEV UL13, showing that the nuclear localization signal of DEV UL13 is a classical importin α- and β-dependent process.

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To determine the role of glycoprotein I (gI) in duck plague virus (DPV), a gI-deleted mutant (BAC-CHv-ΔgI) and a gI-revertant virus (BAC-CHv-ΔgI Rev) were constructed by using a markerless two-step Red recombination system implemented on the DPV genome cloned into a bacterial artificial chromosome (BAC). Mutants were characterized on duck embryo fibroblast (DEF) cells compared with wild-type virus. BAC-CHv-ΔgI produced viral plaques on DEF cells that were on average approximately 57.

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  • CRISPR systems and prokaryotic Argonaute proteins (Agos) play key roles in protecting bacteria and archaea from invading nucleic acids, preventing horizontal gene transfer.
  • The CRISPR system uses an RNA-guided complex to target and cut foreign DNA or RNA, while Agos utilize single-strand DNA or RNA for their targeting.
  • This review explores how these defense mechanisms interact with the process of natural transformation, where external single-stranded DNA is integrated into host genomes, and highlights the complexities of undermining these systems.
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  • Duck enteritis virus (DEV) is part of the Alphaherpesvirinae subfamily, and while some gene characteristics have been reported, information on the DEV UL47 gene is limited.
  • The study identifies the DEV UL47 gene, which encodes a late structural protein that is located in the nucleus of infected cells and has two regions acting as nuclear localization sequences (NLS).
  • Additionally, the pUL47 protein inhibits the production of interferon beta (IFN-β) and downregulates certain interferon-stimulated genes (ISGs) by interacting with STAT1.
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