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Microorganisms Dec 2023The Genus contains viruses pathogenic mainly for chickens, forming the Avian Sarcoma and Leukosis Virus group (ASLV). Cells of most Galliform species, besides chickens,...
The Genus contains viruses pathogenic mainly for chickens, forming the Avian Sarcoma and Leukosis Virus group (ASLV). Cells of most Galliform species, besides chickens, contain genetic elements (endogenous retroviruses, ERVs) that could recombine with other alpharetroviruses or express proteins, complementing defective ASLV, which may successfully replicate and cause disease. However, they are quite unknown, and only ALV-F, from ring-necked pheasants, has been partially published. Upon scrutiny of 53 genomes of different avian species, we found -like sequences only in 12 different Galliformes, including six full-length (7.4-7.6 Kbp) and 27 partial sequences. Phylogenetic studies of the regions studied (LTR, , , and ) consistently resulted in five almost identical clades containing the same ERVs: Clade I (presently known ASLVs); Clade II ( spp. ERVs); Clade IIIa ( ERVs); Clade IIIb ( spp. ERVs); and Clade IV ( spp. ERVs). The low identity scores suggested that each of these Clades may be considered a different species. ORF analysis revealed that putatively encoded proteins would be very similar in length and domains to those of other alpharetroviruses and thus potentially functional. This will undoubtedly contribute to better understanding the biology of defective viruses, especially in wild Galliformes, their evolution, and the danger they may represent for other wild species and the poultry industry.
PubMed: 38257913
DOI: 10.3390/microorganisms12010086 -
3'UTR of ALV-J can affect viral replication through promoting transcription and mRNA nuclear export.Journal of Virology Nov 20233'UTRs can affect gene transcription and post-transcriptional regulation in multiple ways, further influencing the function of proteins in a unique manner. Recently,...
3'UTRs can affect gene transcription and post-transcriptional regulation in multiple ways, further influencing the function of proteins in a unique manner. Recently, ALV-J has been mutating and evolving rapidly, especially the 3'UTR of viral genome. Meanwhile, clinical symptoms caused by ALV-J have changed significantly. In this study, we found that the ALV-J strains containing △-r-TM-type 3'UTR are the most abundant. By constructing ALV-J infectious clones and subgenomic vectors containing different 3'UTRs, we prove that 3'UTRs directly affect viral tissue preference and can promote virus replication as an enhancer. ALV-J strain containing 3'UTR of △-r-TM proliferated fastest in primary cells. All five forms of 3'UTRs can assist intron-containing viral mRNA nuclear export, with similar efficiency. ALV-J mRNA half-life is not influenced by different 3'UTRs. Our results dissect the roles of 3'UTR on regulating viral replication and pathogenicity, providing novel insights into potential anti-viral strategies.
Topics: 3' Untranslated Regions; Active Transport, Cell Nucleus; Gene Expression; Gene Expression Regulation; Virus Replication; Avian Leukosis Virus
PubMed: 37902396
DOI: 10.1128/jvi.01152-23 -
Journal of Virology Nov 2023The synergy of two oncogenic retroviruses is an essential phenomenon in nature. The synergistic replication of ALV-J and REV in poultry flocks increases...
The synergy of two oncogenic retroviruses is an essential phenomenon in nature. The synergistic replication of ALV-J and REV in poultry flocks increases immunosuppression and pathogenicity, extends the tumor spectrum, and accelerates viral evolution, causing substantial economic losses to the poultry industry. However, the mechanism of synergistic replication between ALV-J and REV is still incompletely elusive. We observed that microRNA-155 targets a dual pathway, PRKCI-MAPK8 and TIMP3-MMP2, interacting with the U3 region of ALV-J and REV, enabling synergistic replication. This work gives us new targets to modulate ALV-J and REV's synergistic replication, guiding future research on the mechanism.
Topics: Animals; Reticuloendotheliosis virus; Avian Leukosis; Avian Leukosis Virus; Chickens; Poultry Diseases; MicroRNAs; Virus Replication
PubMed: 37909729
DOI: 10.1128/jvi.00937-23 -
Journal of Virology Aug 2023Avian leukemia virus subgroup J (ALV-J) causes various diseases associated with tumor formation and decreased fertility and induced immunosuppressive disease, resulting...
Avian leukemia virus subgroup J (ALV-J) causes various diseases associated with tumor formation and decreased fertility and induced immunosuppressive disease, resulting in significant economic losses in the poultry industry globally. Virus usually exploits the host cellular machinery for their replication. Although there are increasing evidences for the cellular proteins involving viral replication, the interaction between ALV-J and host proteins leading to the pivotal steps of viral life cycle are still unclear. Here, we reported that ribonucleoside-diphosphate reductase subunit M2 (RRM2) plays a critical role during ALV-J infection by interacting with capsid protein P27 and activating Wnt/β-catenin signaling. We found that the expression of RRM2 is effectively increased during ALV-J infection, and that RRM2 facilitates ALV-J replication by interacting with viral capsid protein P27. Furthermore, ALV-J P27 activated Wnt/β-catenin signaling by promoting β-catenin entry into the nucleus, and RRM2 activated Wnt/β-catenin signaling by enhancing its phosphorylation at Ser18 during ALV-J infection. These data suggest that the upregulation of RRM2 expression by ALV-J infection favors viral replication in host cells via activating Wnt/β-catenin signaling. IMPORTANCE Our results revealed a novel mechanism by which RRM2 facilitates ALV-J growth. That is, the upregulation of RRM2 expression by ALV-J infection favors viral replication by interacting with capsid protein P27 and activating Wnt/β-catenin pathway in host cells. Furthermore, the phosphorylation of serine at position 18 of RRM2 was verified to be the important factor regulating the activation of Wnt/β-catenin signaling. This study provides insights for further studies of the molecular mechanism of ALV-J infection.
Topics: Animals; Avian Leukosis; Avian Leukosis Virus; beta Catenin; Capsid Proteins; Chickens; Wnt Signaling Pathway; Ribonucleoside Diphosphate Reductase
PubMed: 37582207
DOI: 10.1128/jvi.00267-23 -
Veterinary Microbiology Sep 2023While the presence of host cell proteins in virions and their role in viral life cycles have been demonstrated in various viruses, such characteristics have remained...
While the presence of host cell proteins in virions and their role in viral life cycles have been demonstrated in various viruses, such characteristics have remained largely unknown in avian leukosis virus (ALV). To investigate whether this is the case in ALV, we purified high-integrity and high-purity virions from the avian leukosis virus subgroup J (ALV-J) and subjected them to proteome analysis using nano LC-MS/MS. This analysis identified 53 cellular proteins that are incorporated into mature ALV-J virions, and we verified the reliability of the packaged cellular proteins through subtilisin digestion and immunoblot analysis. Functional annotation revealed the potential functions of these proteins in the viral life cycle and tumorigenesis. Overall, our findings have important implications for understanding the interaction between ALV-J and its host, and provide new insights into the cellular requirements that define ALV-J infection.
Topics: Animals; Chickens; Avian Leukosis Virus; Tandem Mass Spectrometry; Proteomics; Reproducibility of Results; Avian Leukosis
PubMed: 37536160
DOI: 10.1016/j.vetmic.2023.109821 -
Journal of Molecular Biology Aug 2023Biomolecular condensates (BMCs) play important roles incellular structures includingtranscription factories, splicing speckles, and nucleoli. BMCs bring together...
Biomolecular condensates (BMCs) play important roles incellular structures includingtranscription factories, splicing speckles, and nucleoli. BMCs bring together proteins and other macromolecules, selectively concentrating them so that specific reactions can occur without interference from the surrounding environment. BMCs are often made up of proteins that contain intrinsically disordered regions (IDRs), form phase-separated spherical puncta, form liquid-like droplets that undergo fusion and fission, contain molecules that are mobile, and are disrupted with phase-dissolving drugs such as 1,6-hexanediol. In addition to cellular proteins, many viruses, including influenza A, SARS-CoV-2, and human immunodeficiency virus type 1 (HIV-1) encode proteins that undergo phase separation and rely on BMC formation for replication. In prior studies of the retrovirus Rous sarcoma virus (RSV), we observed that the Gag protein forms discrete spherical puncta in the nucleus, cytoplasm, and at the plasma membrane that co-localize with viral RNA and host factors, raising the possibility that RSV Gag forms BMCs that participate in the intracellular phase of the virion assembly pathway. In our current studies, we found that Gag contains IDRs in the N-terminal (MAp2p10) and C-terminal (NC) regions of the protein and fulfills many criteria of BMCs. Although the role of BMC formation in RSV assembly requires further study, our results suggest the biophysical properties of condensates are required for the formation of Gag complexes in the nucleus and the cohesion of these complexes as they traffic through the nuclear pore, into the cytoplasm, and to the plasma membrane, where the final assembly and release of virus particles occurs.
Topics: Humans; Biomolecular Condensates; Gene Products, gag; Rous sarcoma virus; Intrinsically Disordered Proteins; Phase Transition
PubMed: 37328094
DOI: 10.1016/j.jmb.2023.168182 -
Poultry Science May 2024Endogenous retroviruses (ERV) are viral genomes integrated into the host genome and can be stably inherited. Although ERV sequences have been reported in some avian...
Endogenous retroviruses (ERV) are viral genomes integrated into the host genome and can be stably inherited. Although ERV sequences have been reported in some avian species' genome, the duck endogenous retroviruses (DERV) genome has yet to be quantified. This study aimed to identify ERV sequences and characterize genes near ERVs in the duck genome by utilizing LTRhavest and LTRdigest tools to forecast the duck genome and analyze the distribution of ERV copies. The results revealed 1,607, 2,031, and 1,908 full-length ERV copies in the Pekin duck (ZJU1.0), Mallard (CAU_wild_1.0), and Shaoxing duck (CAU_laying_1.0) genomes, respectively, with average lengths of 7,046, 7,027, and 6,945 bp. ERVs are mainly distributed on the 1, 2, and sex chromosomes. Phylogenetic analysis demonstrated the presence of Betaretrovirus in 3 duck genomes, whereas Alpharetrovirus was exclusively identified in the Shaoxing duck genome. Through screening, 596, 315, and 343 genes adjacent to ERV were identified in 3 duck genomes, respectively, and their functions of ERV neighboring genes were predicted. Functional enrichment analysis of ERV-adjacent genes revealed enrichment for Focal adhesion, Calcium signaling pathway, and Adherens junction in 3 duck genomes. The overlapped genes were highly expressed in 8 tissues (brain, fat, heart, kidney, liver, lung, skin, and spleen) of 8-wk-old Mallard, revealing their important expression in different tissues. Our study provides a new perspective for understanding the quantity and function of DERVs, and may also provide important clues for regulating nearby genes and affecting the traits of organisms.
Topics: Animals; Ducks; Genome; Phylogeny; Endogenous Retroviruses
PubMed: 38447307
DOI: 10.1016/j.psj.2024.103543 -
Journal of Wildlife Diseases Jan 2024Lymphoproliferative disease virus (LPDV) and reticuloendotheliosis virus (REV) are oncogenic retroviruses that can cause disease in wild and domestic fowl....
Lymphoproliferative disease virus (LPDV) and reticuloendotheliosis virus (REV) are oncogenic retroviruses that can cause disease in wild and domestic fowl. Lymphoproliferative disease virus infections are common and widespread in Wild Turkeys (Meleagris gallopavo) in the US and east-central Canada, while REV has been detected worldwide in numerous avian host species. We tested tissues (spleen, liver, and/or bone marrow, plus neoplastic tissue, if present) from 172 Wild Turkeys that underwent necropsy from December 2018 through October 2021 for both viruses using PCR. We evaluated demographic, geographic, temporal, and seasonal data by chi-square test of independence and logistic regression for turkeys infected with LPDV and/or REV. At least one of these retroviruses was detected in 80.8% (139/172) of Wild Turkeys from 15 US states, with significantly more turkeys being positive for LPDV (72.1%, 124/172) versus REV (43.6%, 75/172; P<0.001). Both viruses (coinfections) were detected in 34.9% (60/172) of turkeys. Among LPDV-infected turkeys (including coinfections), bone marrow had the highest detection rate (38/58, 65.5%), significantly higher than spleen (30/58, 51.7%) and liver (20/58, 34.5%; P<0.001). In REV-infected turkeys, bone marrow had the highest detection rate (24/58, 41.4%). All three tissues (spleen, liver, bone marrow) concurrently tested positive in most (15/25, 60%) REV-infected turkeys. These results suggest LPDV tissue tropism for bone marrow, whereas REV may have broader tissue tropism. Histopathology consistent with lymphoid proliferation and/or neoplasia characteristic of lymphoproliferative disease was evident in 29/172 (16.9%) turkeys assessed, including two REV-only-infected turkeys. Season was significantly associated with LPDV prevalence (highest in winter); year and season were both significantly associated with REV prevalence (highest in 2020 and winter). These data contribute to optimizing diagnostic strategies that may aid in pathogen monitoring and improve detections to increase our understanding of the potential impacts of these viruses on Wild Turkey populations.
Topics: Animals; Reticuloendotheliosis virus; Coinfection; Bird Diseases; Alpharetrovirus; Retroviridae; Turkeys
PubMed: 37972643
DOI: 10.7589/JWD-D-23-00012 -
Scientific Reports Feb 2024Lymphoid leukosis is a poultry neoplastic disease caused by avian leukosis virus (ALV) and is characterized by high morbidity and variable mortality rates in chicks....
Lymphoid leukosis is a poultry neoplastic disease caused by avian leukosis virus (ALV) and is characterized by high morbidity and variable mortality rates in chicks. Currently, no effective treatment and vaccination is the only means to control it. This study exploited the immunoinformatics approaches to construct multi-epitope vaccine against ALV. ABCpred and IEDB servers were used to predict B and T lymphocytes epitopes from the viral proteins, respectively. Antigenicity, allergenicity and toxicity of the epitopes were assessed and used to construct the vaccine with suitable adjuvant and linkers. Secondary and tertiary structures of the vaccine were predicted, refined and validated. Structural errors, solubility, stability, immune simulation, dynamic simulation, docking and in silico cloning were also evaluated.The constructed vaccine was hydrophilic, antigenic and non-allergenic. Ramchandran plot showed most of the residues in the favored and additional allowed regions. ProsA server showed no errors in the vaccine structure. Immune simulation showed significant immunoglobulins and cytokines levels. Stability was enhanced by disulfide engineering and molecular dynamic simulation. Docking of the vaccine with chicken's TLR7 revealed competent binding energies.The vaccine was cloned in pET-30a(+) vector and efficiently expressed in Escherichia coli. This study provided a potent peptide vaccine that could assist in tailoring a rapid and cost-effective vaccine that helps to combat ALV. However, experimental validation is required to assess the vaccine efficiency.
Topics: Animals; Molecular Docking Simulation; Avian Leukosis Virus; Protein Subunit Vaccines; Immunoinformatics; Chickens; Epitopes, T-Lymphocyte; Molecular Dynamics Simulation; Epitopes, B-Lymphocyte; Vaccines, Subunit; Computational Biology
PubMed: 38311642
DOI: 10.1038/s41598-024-53048-6 -
Journal of Veterinary Diagnostic... Sep 2023The fowl glioma-inducing virus prototype (FGVp) and its variants, which belong to avian leukosis virus subgroup A (ALV-A), induce cardiomyocyte abnormalities and gliomas...
The fowl glioma-inducing virus prototype (FGVp) and its variants, which belong to avian leukosis virus subgroup A (ALV-A), induce cardiomyocyte abnormalities and gliomas in chickens. However, the molecular mechanisms underlying these myocardial changes remain unclear, and ALV-induced tumorigenesis, which is caused by proviral insertional mutagenesis, does not explain the early development of cardiac changes in infected chickens. We established a quantitative PCR (qPCR) assay to measure ALV-A proviral loads in the brains and hearts of FGV-infected Japanese bantam chickens and compared these results with morphologic lesions. Four of 22 bantams had both gliomas and cardiac lesions. Hearts with cardiac lesions had a higher proviral load (10.3 ± 2.7 proviral copies/nucleus) than those without cardiac lesions (0.4 ± 0.4), suggesting that the proviral load in hearts is correlated with the frequency of myocardial changes. Our qPCR method may be useful in the study of ALV-induced cardiomyocyte abnormalities.
Topics: Animals; Avian Leukosis Virus; Chickens; Glioma; Poultry Diseases; Proviruses; Viral Load
PubMed: 37452573
DOI: 10.1177/10406387231186954