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Ren G, Wang Z, Hu X. Effects of Ectodomain Sequences between HR1 and HR2 of F 1 Protein on the Specific Membrane Fusion in Paramyxoviruses. Intervirology 2006; 50:115-22. [PMID: 17191013 DOI: 10.1159/000098237] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Accepted: 07/27/2006] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To explore the effects of ectodomain sequences between HR1 and HR2 of F1 protein on the specific interaction with its homologous hemagglutinin-neuraminidase (HN) in paramyxoviruses. METHODS Site-directed mutagenesis was used to obtain mutants containing new enzyme sites on the F genes of Newcastle disease virus (NDV) and human parainfluenza virus (hPIV), and four DNA segments located between the HR1 and HR2 (NDV F-1, hPIV F-1, NDV F-2 and hPIV F-2) were obtained by cutting mutant F genes with specific endonucleases. Gene recombination was used to get chimeric F proteins NDV-C1 and hPIV-C1 by exchanging NDV F-1 and hPIV F-1 each other, and NDV-C2 and hPIV-C2 were also obtained by the same way. All the mutants and chimeric F proteins were co-expressed with their homologous or heterologous HN proteins in eukaryocytes. The fusion functions were assayed with Giemsa staining and reporter gene method for qualitative and quantitative analyses, respectively. The cell surface expression of F proteins was assayed with fluorescence-activated cell sorter (FACS) for quantitative analysis. RESULTS All the mutants of F proteins had the same functions as their relevant wild types. Chimeric F proteins NDV-C1 and hPIV-C1 had 76.34 and 65.82% of fusion activities, and NDV-C2 and hPIV-C2 had 96.25 and 93.78% of fusion activities, respectively, as compared with their relevant wild types. The analysis of FACS indicated that all the mutants and chimeric F proteins had almost the same expression efficiencies as their relevant wild types. CONCLUSIONS The segments of NDV F-1 and hPIV F-1 were important for their specific membrane fusion, but NDV F-2 and hPIV F-2 were not.
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102
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Laliberte JP, McGinnes LW, Peeples ME, Morrison TG. Integrity of membrane lipid rafts is necessary for the ordered assembly and release of infectious Newcastle disease virus particles. J Virol 2006; 80:10652-62. [PMID: 17041223 PMCID: PMC1641742 DOI: 10.1128/jvi.01183-06] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Accepted: 08/05/2006] [Indexed: 11/20/2022] Open
Abstract
Membrane lipid raft domains are thought to be sites of assembly for many enveloped viruses. The roles of both classical lipid rafts and lipid rafts associated with the membrane cytoskeleton in the assembly of Newcastle disease virus (NDV) were investigated. The lipid raft-associated proteins caveolin-1, flotillin-2, and actin were incorporated into virions, while the non-lipid raft-associated transferrin receptor was excluded. Kinetic analyses of the distribution of viral proteins in lipid rafts, as defined by detergent-resistant membranes (DRMs), in non-lipid raft membranes, and in virions showed an accumulation of HN, F, and NP viral proteins in lipid rafts early after synthesis. Subsequently, these proteins exited the DRMs and were recovered quantitatively in purified virions, while levels of these proteins in detergent-soluble cell fractions remained relatively constant. Cholesterol depletion of infected cells drastically altered the association of viral proteins with DRMs and resulted in an enhanced release of virus particles with reduced infectivity. Decreased infectivity was not due to effects on subsequent virus entry, since the extraction of cholesterol from intact virus did not significantly reduce infectivity. Particles released from cholesterol-depleted cells had very heterogeneous densities and altered ratios of NP and glycoproteins, demonstrating structural abnormalities which potentially contributed to their lowered infectivity. Taken together, these results indicate that lipid rafts, including cytoskeleton-associated lipid rafts, are sites of NDV assembly and that these domains are important for ordered assembly and release of infectious Newcastle disease virus particles.
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103
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Pantua HD, McGinnes LW, Peeples ME, Morrison TG. Requirements for the assembly and release of Newcastle disease virus-like particles. J Virol 2006; 80:11062-73. [PMID: 16971425 PMCID: PMC1642154 DOI: 10.1128/jvi.00726-06] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Accepted: 08/29/2006] [Indexed: 01/05/2023] Open
Abstract
Paramyxoviruses, such as Newcastle disease virus (NDV), assemble in and bud from plasma membranes of infected cells. To explore the role of each of the NDV structural proteins in virion assembly and release, virus-like particles (VLPs) released from avian cells expressing all possible combinations of the nucleoprotein (NP), membrane or matrix protein (M), an uncleaved fusion protein (F-K115Q), and hemagglutinin-neuraminidase (HN) protein were characterized for densities, protein content, and efficiencies of release. Coexpression of all four proteins resulted in the release of VLPs with densities and efficiencies of release (1.18 to 1.16 g/cm(3) and 83.8% +/- 1.1%, respectively) similar to those of authentic virions. Expression of M protein alone, but not NP, F-K115Q, or HN protein individually, resulted in efficient VLP release, and expression of all different combinations of proteins in the absence of M protein did not result in particle release. Expression of any combination of proteins that included M protein yielded VLPs, although with different densities and efficiencies of release. To address the roles of NP, F, and HN proteins in VLP assembly, the interactions of proteins in VLPs formed with different combinations of viral proteins were characterized by coimmunoprecipitation. The colocalization of M protein with cell surface F and HN proteins in cells expressing all combinations of viral proteins was characterized. Taken together, the results show that M protein is necessary and sufficient for NDV budding. Furthermore, they suggest that M-HN and M-NP interactions are responsible for incorporation of HN and NP proteins into VLPs and that F protein is incorporated indirectly due to interactions with NP and HN protein.
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104
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Matsui K, Kumagai Y, Kato H, Sato S, Kawagoe T, Uematsu S, Takeuchi O, Akira S. Cutting Edge: Role of TANK-Binding Kinase 1 and Inducible IκB Kinase in IFN Responses against Viruses in Innate Immune Cells. THE JOURNAL OF IMMUNOLOGY 2006; 177:5785-9. [PMID: 17056502 DOI: 10.4049/jimmunol.177.9.5785] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
TANK-binding kinase 1 (TBK1) and inducible IkappaB kinase (IKK-i) are involved in the activation of transcription factors inducing the production of type I IFNs. Although TBK1, but not IKK-i, is critical for LPS-induced IFN induction, the role of these kinases in the responses against viral infection is yet to be determined. In this study, we show that type I IFN production against various RNA viruses was completely abrogated in conventional dendritic cells (DCs) and macrophages induced from fetal liver cells lacking both TBK1 and IKK-i, whereas considerable amounts of IFN were produced in cells lacking either of them. Microarray analysis revealed that various IFN-inducible genes were also regulated by the kinases. In contrast, Fms-like tyrosine kinase 3 ligand-induced DCs produced IFN-alpha even in the absence of both TBK1 and IKK-i. Thus, these two kinases are essential and compensate each other for the regulation of IFN responses in innate immune cells except plasmacytoid DCs.
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105
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Elankumaran S, Rockemann D, Samal SK. Newcastle disease virus exerts oncolysis by both intrinsic and extrinsic caspase-dependent pathways of cell death. J Virol 2006; 80:7522-34. [PMID: 16840332 PMCID: PMC1563725 DOI: 10.1128/jvi.00241-06] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Newcastle disease virus (NDV), an avian paramyxovirus, is tumor selective and intrinsically oncolytic. Here, we present evidence that genetically modified, recombinant NDV strains are cytotoxic to human tumor cell lines of ecto-, endo-, and mesodermal origin. We show that cytotoxicity against tumor cells is due to multiple caspase-dependent pathways of apoptosis independent of interferon signaling competence. The signaling pathways of NDV-induced, cancer cell-selective apoptosis are not well understood. We demonstrate that NDV triggers apoptosis by activating the mitochondrial/intrinsic pathway and that it acts independently of the death receptor/extrinsic pathway. Caspase-8-methylated SH-SY5Y neuroblastoma cells are as sensitive to NDV as other caspase-8-competent cells. This demonstrates that NDV is likely to act primarily through the mitochondrial death pathway. NDV infection results in the loss of mitochondrial membrane potential and the subsequent release of the mitochondrial protein cytochrome c, but the second mitochondrion-derived activator of caspase (Smac/DIABLO) is not released. In addition, we describe early activation of caspase-9 and caspase-3. In contrast, cleavage of caspase-8, which is predominantly activated by the death receptor pathway, is a TNF-related, apoptosis-inducing ligand (TRAIL)-induced late event in NDV-mediated apoptosis of tumor cells. Our data, therefore, indicate that the death signal(s) generated by NDV in tumor cells ultimately converges at the mitochondria and that it acts independently of the death receptor pathway. Our cytotoxicity studies demonstrate that recombinant NDV could be developed as a cancer virotherapy agent, either alone or in combination with therapeutic transgenes. We have also shown that trackable oncolytic NDV could be developed without any reduction in oncolytic efficacy.
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106
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Calderón NL, Galundo-Muñiz F, Ortiz M, Lomniczi B, Fehervari T, Paasch LH. Thrombocytopenia in Newcastle disease: haematological evaluation and histological study of bone marrow. Acta Vet Hung 2006; 53:507-13. [PMID: 16363152 DOI: 10.1556/avet.53.2005.4.11] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A Newcastle disease virus (NDV) isolated in Mexico and called Chimalhuacan strain was characterised by gene F restriction enzyme analysis and found to be a genotype II velogenic virus. Haematological evaluations and histological studies of bone marrow were conducted on chickens experimentally infected with the Chimalhuacan virus and on control chickens. Within 72 hours post infection (hpi), a 50% decrease in thrombocyte and monocyte counts and a complete cellular depletion in bone marrow islands were evident in the infected group. These findings suggest that the Chimalhuacan strain of NDV causes an early and severe damage of the haematopoietic cells including thrombocyte precursors, which might explain the marked thrombocytopenia detected in early stages of this disease.
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107
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Krishnamurthy S, Takimoto T, Scroggs RA, Portner A. Differentially regulated interferon response determines the outcome of Newcastle disease virus infection in normal and tumor cell lines. J Virol 2006; 80:5145-55. [PMID: 16698995 PMCID: PMC1472132 DOI: 10.1128/jvi.02618-05] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Accepted: 03/20/2006] [Indexed: 01/14/2023] Open
Abstract
Newcastle disease virus (NDV) is a negative-strand RNA virus with oncolytic activity against human tumors. Its effectiveness against tumors and safety in normal tissue have been demonstrated in several clinical studies. Here we show that the spread of NDV infection is drastically different in normal cell lines than in tumor cell lines and that the two cell types respond differently to beta interferon (IFN-beta) treatment. NDV rapidly replicated and killed HT-1080 human fibrosarcoma cells but spread poorly in CCD-1122Sk human skin fibroblast cells. Pretreatment with endogenous or exogenous IFN-beta completely inhibited NDV replication in normal cells but had little or no effect in tumor cells. Thus, the outcome of NDV infection appeared to depend on the response of uninfected cells to IFN-beta. To investigate their differences in IFN responsiveness, we analyzed and compared the expression and activation of components of the IFN signal transduction pathway in these two types of cells. The levels of phosphorylated STAT1 and STAT2 and that of the ISGF3 complex were markedly reduced in IFN-beta-treated tumor cells. Moreover, cDNA microarray analysis revealed significantly fewer IFN-regulated genes in the HT-1080 cells than in the CDD-1122Sk cells. This finding suggests that tumor cells demonstrate a less-than-optimum antiviral response because of a lesion in their IFN signal transduction pathway. The rapid spread of NDV in HT-1080 cells appears to be caused by their deficient expression of anti-NDV proteins upon exposure to IFN-beta.
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108
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Alexander DJ, Manvell RJ, Parsons G. Newcastle disease virus (strain Herts 33/56) in tissues and organs of chickens infected experimentally. Avian Pathol 2006; 35:99-101. [PMID: 16595300 DOI: 10.1080/03079450600597444] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Six-week-old susceptible specific pathogen free chickens were infected intranasally with the virulent Newcastle disease virus strain Herts 33/56 and the levels of virus present in blood, faeces, breast muscle, leg muscle and a pool of heart/kidney/spleen were estimated in birds killed humanely at each day post inoculation. Highest titres were recorded at day 4 post inoculation when titres of virus were 10(6) median egg infectious doses (EID50)/g in the heart/kidney/spleen pool, 10(4.2) EID50/g in the leg muscle and 10(4) EID50/g in the breast muscle and faeces. A median oral infectious dose of Newcastle disease virus strain Herts 33/56 for 3-week-old chickens was estimated to be equivalent to 10(4) EID50.
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109
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Porotto M, Fornabaio M, Greengard O, Murrell MT, Kellogg GE, Moscona A. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 2006; 80:1204-13. [PMID: 16414997 PMCID: PMC1346948 DOI: 10.1128/jvi.80.3.1204-1213.2006] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The hemagglutinin-neuraminidase (HN) protein of paramyxoviruses carries out three different activities: receptor binding, receptor cleaving (neuraminidase), and triggering of the fusion protein. These three discrete properties each affect the ability of HN to promote viral fusion and entry. For human parainfluenza type 3, one bifunctional site on HN can carry out both binding and neuraminidase, and the receptor mimic, zanamivir, impairs viral entry by blocking receptor binding. We report here that for Newcastle disease virus, the HN receptor avidity is increased by zanamivir, due to activation of a second site that has higher receptor avidity. Only certain receptor mimics effectively activate the second site (site II) via occupation of site I; yet without activation of this second site, binding is mediated entirely by site I. Computational modeling designed to complement the experimental approaches suggests that the potential for small molecule receptor mimics to activate site II, upon binding to site I, directly correlates with their predicted strengths of interaction with site I. Taken together, the experimental and computational data show that the molecules with the strongest interactions with site I-zanamivir and BCX 2798-lead to the activation of site II. The finding that site II, once activated, shows higher avidity for receptor than site I, suggests paradigms for further elucidating the regulation of HN's multiple functions in the viral life cycle.
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110
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Melanson VR, Iorio RM. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 2006; 80:623-33. [PMID: 16378965 PMCID: PMC1346869 DOI: 10.1128/jvi.80.2.623-633.2006] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Most paramyxovirus fusion (F) proteins require the coexpression of the homologous attachment (HN) protein to promote membrane fusion, consistent with the existence of a virus-specific interaction between the two proteins. Analysis of the fusion activities of chimeric HN proteins indicates that the stalk region of the HN spike determines its F protein specificity, and analysis of a panel of site-directed mutants indicates that the F-interactive site resides in this region. Here, we use the addition of oligosaccharides to further explore the role of the HN stalk in the interaction with F. N-glycans were individually added at several positions in the stalk to determine their effects on the activities of HN, as well as its structure. N-glycan addition at positions 69 and 77 in the stalk specifically blocks fusion and the HN-F interaction without affecting either HN structure or its other activities. N-glycans added at other positions in the stalk modulate activities that reside in the globular head of HN. This correlates with an alteration of the tetrameric structure of the protein, as indicated by sucrose gradient sedimentation analyses. Finally, N-glycan addition in another region of HN (residues 124 to 152), predicted by a peptide-based analysis to mediate the interaction with F, does not significantly reduce the level of fusion, arguing strongly against this site being part of the F-interactive domain in HN. Our data support the idea that the F-interactive site on HN is defined by the stalk region of the protein.
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111
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Todo T. [Brain tumor therapy using replication--competent virus vectors]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2005; 63 Suppl 9:504-9. [PMID: 16201572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
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112
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Zhang PY, Cao DJ, Hu LH. [Study of Newcastle disease virus killing hepatocellular carcinoma cells in vitro]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2005; 13:467-8. [PMID: 15975291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
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113
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Bell J. Replicating oncolytic virus therapeutics - Third International Meeting. IDRUGS : THE INVESTIGATIONAL DRUGS JOURNAL 2005; 8:360-3. [PMID: 15883909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
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114
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Marcos F, Ferreira L, Cros J, Park MS, Nakaya T, García-Sastre A, Villar E. Mapping of the RNA promoter of Newcastle disease virus. Virology 2005; 331:396-406. [PMID: 15629782 DOI: 10.1016/j.virol.2004.10.040] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Revised: 08/25/2004] [Accepted: 10/25/2004] [Indexed: 11/18/2022]
Abstract
The RNA promoters of the genome and antigenome of Newcastle disease virus (NDV) were studied by mutational analysis of their 3' terminal ends. Similarly to other paramyxoviruses, NDV RNA replication follows the rule of six, and the genomic and antigenomic promoters require two discontinuous regions: conserved region I (first 18 nucleotides) and conserved region II (nucleotides 73-90). Proper spacing between those regions and the phase of six in region II is critical for efficient RNA promoter activity. As expected, the gene start signal at the 3' end of the NDV genome was required for mRNA transcription, but not for RNA replication. Surprisingly, mutation of the polyadenylation signal in the 5' end did not affect gene expression transcription. Although the conserved region I of NDV (avulavirus) promoter appears to be more similar to that of Sendai virus (SeV) (respirovirus), conserved region II is analogous to that of rubulaviruses.
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115
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Li J, Melanson VR, Mirza AM, Iorio RM. Decreased dependence on receptor recognition for the fusion promotion activity of L289A-mutated newcastle disease virus fusion protein correlates with a monoclonal antibody-detected conformational change. J Virol 2005; 79:1180-90. [PMID: 15613345 PMCID: PMC538552 DOI: 10.1128/jvi.79.2.1180-1190.2005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It has been shown that the L289A-mutated Newcastle disease virus (NDV) fusion (F) protein gains the ability to promote fusion of Cos-7 cells independent of the viral hemagglutinin-neuraminidase (HN) protein and exhibits a 50% enhancement in HN-dependent fusion over wild-type (wt) F protein. Here, we show that HN-independent fusion by L289A-F is not exhibited in BHK cells or in several other cell lines. However, similar to the results in Cos-7 cells, the mutated protein plus HN does promote 50 to 70% more fusion above wt levels in all of the cell lines tested. L289A-F protein exhibits the same specificity as the wt F protein for the homologous HN protein, as well as NDV-human parainfluenza virus 3 HN chimeras. The mutated F protein promotes fusion more effectively than the wt when it is coexpressed with either the chimeras or HN proteins deficient in receptor recognition activity. In addition, its fusogenic activity is significantly more resistant to removal of sialic acid on target cells. These findings are consistent with the demonstration that L289A-F interacts more efficiently with wt and mutated HN proteins than does wt F by a cell surface coimmunoprecipitation assay. Taken together, these findings indicate that L289A-F promotes fusion by a mechanism analogous to that of the wt protein with respect to the HN-F interaction but is less dependent on the attachment activity of HN. The phenotype of the mutated F protein correlates with a conformational change in the protein detectable by two different monoclonal antibodies. This conformational change may reflect a destabilization of F structure induced by the L289A substitution, which may in turn indicate a lower energy requirement for fusion activation.
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116
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Małaczewska J, Rotkiewicz Z. Biological properties of Roakin strain of NDV and TK900 strain of ADV after serial passages in CECC in the presence of methisoprinol and KLP-602. Pol J Vet Sci 2005; 8:23-8. [PMID: 15794470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Twenty serial passages of the TK900 strain of Aujeszky's disease virus (ADV) and the Roakin strain of Newcastle disease virus (NDV) were made in a chicken embryo cell culture (CECC), in the presence of two antiviral agents: Methisoprinol and KLP-602. The physicochemical properties of passaged viruses were determined. The results obtained suggest that Methisoprinol causes changes in the structure of viral proteins, whereas KLP-602 affects the envelope-dependent properties of the virus. It was also found that the alternations observed in passaged viruses were temporary phenotypic changes only, and not a consequence of permanent transformations of their genotypes.
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117
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Małaczewska J, Rotkiewicz Z. Effect of methisoprinol and KLP-602 on virus replication in chicken embryos. Pol J Vet Sci 2005; 8:289-94. [PMID: 16385853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The aim of the present study was to examine the effects of two immunomodulators (KLP-602 and Methisoprinol) on the proliferation of two strains of Newcastle disease virus in chick embryos. The effect of the maximum tolerable doses of both drugs (Methisoprinol--6 mg/embryo, KLP-602--5 mg/embryo) on lymphocyte reactivity were determined prior to the experiment. Both drugs inhibited the replication of the Roakin strain of NDV in various experimental designs, but neither of them affected the proliferation of the LaSota strain of NDV.
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118
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Bousse TL, Taylor G, Krishnamurthy S, Portner A, Samal SK, Takimoto T. Biological significance of the second receptor binding site of Newcastle disease virus hemagglutinin-neuraminidase protein. J Virol 2004; 78:13351-5. [PMID: 15542686 PMCID: PMC525016 DOI: 10.1128/jvi.78.23.13351-13355.2004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The paramyxovirus hemagglutinin-neuraminidase (HN) is a multifunctional protein responsible for attachment to receptors containing sialic acid, neuraminidase (NA) activity, and the promotion of membrane fusion, which is induced by the fusion protein. Analysis of the three-dimensional structure of Newcastle disease virus (NDV) HN protein revealed the presence of a large pocket, which mediates both receptor binding and NA activities. Recently, a second sialic acid binding site on HN was revealed by cocrystallization of the HN with a thiosialoside Neu5Ac-2-S-alpha(2,6)Gal1OMe, suggesting that NDV HN contains an additional sialic acid binding site. To evaluate the role of the second binding site on the life cycle of NDV, we rescued mutant viruses whose HNs were mutated at Arg516, a key residue that is involved in the second binding site. Loss of the second binding site on mutant HNs was confirmed by the hemagglutination inhibition test, which uses an inhibitor designed to block the NA active site. Characterization of the biological activities of HN showed that the mutation at Arg516 had no effect on NA activity. However, the fusion promotion activity of HN was substantially reduced by the mutation. Furthermore, the mutations at Arg516 slowed the growth rate of virus in tissue culture cells. These results suggest that the second binding site facilitates virus infection and growth by enhancing the fusion promotion activity of the HN.
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119
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Melanson VR, Iorio RM. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 2004; 78:13053-61. [PMID: 15542657 PMCID: PMC525001 DOI: 10.1128/jvi.78.23.13053-13061.2004] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus mediates attachment to sialic acid receptors, as well as cleavage of the same moiety. HN also interacts with the other viral glycoprotein, the fusion (F) protein, to promote membrane fusion. The ectodomain of the HN spike consists of a stalk and a terminal globular head. The most conserved part of the stalk consists of two heptad repeats separated by a nonhelical intervening region (residues 89 to 95). Several amino acid substitutions for a completely conserved proline residue in this region not only impair fusion and the HN-F interaction but also decrease neuraminidase activity in the globular domain, suggesting that the substitutions may alter HN structure. Substitutions for L94 also interfere with fusion and the HN-F interaction but have no significant effect on any other HN function. Amino acid substitutions at other positions in the intervening region also modulate only fusion. In all cases, diminished fusion correlates with a decreased ability of the mutated HN protein to interact with F at the cell surface. These findings indicate that the intervening region is critical to the role of HN in the promotion of fusion and may be directly involved in its interaction with the homologous F protein.
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120
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Mi ZQ, Jin NY, Sun YC, Li X, Lian H, Li J, Guan GF. [Antitumor research on mouse melanoma with combined application of Newcastle disease virus and its HN gene]. AI ZHENG = AIZHENG = CHINESE JOURNAL OF CANCER 2004; 23:910-3. [PMID: 15301713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
BACKGROUND & OBJECTIVE Although Newcastle disease virus (NDV) shows antitumor effect on many tumors, its mechanism is unclear. Hemagglutinin-neuraminidase (HN) gene was found to play an important role in NDV antitumor effect and HN protein located on tumor cell surface. This research was to evaluate the possibility of HN protein as a foreign antigen of tumor cell and the antitumor effect of the combined application of HN gene and NDV. METHODS C57BL/6 mice were subcutaneously inoculated with 2 x 10(5) B16 tumor cells in the right hindlimb. Combination group: on 2nd day post-inoculation, the recombinant plasmid containing HN gene was injected intramuscularly in the left hindlimb; on 7th day post-inoculation, 2 x 10(9) pfu NDV was administrated intratumorally. The alone HN gene group, NDV group, and PBS control group were treated as above. The antitumor effect was observed through tumor suppression rate, the antitumor mechanisms were researched with specific cytotoxic T lymphocyte (CTL) assay, and the expression determination of HN protein, ICAM-I, and CD48 on the B16 tumor cells. RESULTS The antitumor efficacy of the combined application of NDV and its HN gene increased compared with NDV,and its HN gene alone, the tumor suppression rates were 82.8%, 41.0%, and 56.6%; the specific CTL activity were 18.4%, 10.1%, and 4.4%, respectively. Furthermore, the expression of HN gene had been detected, and the expression of ICAM-I and CD48 were up-regulated on the tumor cells after NDV injection. CONCLUSION HN protein located on the surface of tumor cells and mediated the specific repulsion to tumor cells; the antitumor efficacy increased after the combined application of NDV and its HN gene.
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Li J, Quinlan E, Mirza A, Iorio RM. Mutated form of the Newcastle disease virus hemagglutinin-neuraminidase interacts with the homologous fusion protein despite deficiencies in both receptor recognition and fusion promotion. J Virol 2004; 78:5299-310. [PMID: 15113911 PMCID: PMC400365 DOI: 10.1128/jvi.78.10.5299-5310.2004] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Newcastle disease virus (NDV) hemagglutinin-neuraminidase (HN) protein mediates attachment to cellular receptors. The fusion (F) protein promotes viral entry and spread. However, fusion is dependent on a virus-specific interaction between the two proteins that can be detected at the cell surface by a coimmunoprecipitation assay. A point mutation of I175E in the neuraminidase (NA) active site converts the HN of the Australia-Victoria isolate of the virus to a form that can interact with the F protein despite negligible receptor recognition and fusion-promoting activities. Thus, I175E-HN could represent a fusion intermediate in which HN and F are associated and primed for the promotion of fusion. Both the attachment and fusion-promoting activities of this mutant HN protein can be rescued either by NA activity contributed by another HN protein or by a set of four substitutions at the dimer interface. These substitutions were identified by the evaluation of chimeras composed of segments from HN proteins derived from two different NDV strains. These findings suggest that the I175E substitution converts HN to an F-interactive form, but it is one for which receptor binding is still required for fusion promotion. The data also indicate that the integrity of the HN dimer interface is critical to its receptor recognition activity.
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Huang Z, Panda A, Elankumaran S, Govindarajan D, Rockemann DD, Samal SK. The hemagglutinin-neuraminidase protein of Newcastle disease virus determines tropism and virulence. J Virol 2004; 78:4176-84. [PMID: 15047833 PMCID: PMC374304 DOI: 10.1128/jvi.78.8.4176-4184.2004] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) plays a crucial role in the process of infection. However, the exact contribution of the HN gene to NDV pathogenesis is not known. In this study, the role of the HN gene in NDV virulence was examined. By use of reverse genetics procedures, the HN genes of a virulent recombinant NDV strain, rBeaudette C (rBC), and an avirulent recombinant NDV strain, rLaSota, were exchanged. The hemadsorption and neuraminidase activities of the chimeric viruses showed significant differences from those of their parental strains, but heterotypic F and HN pairs were equally effective in fusion promotion. The tissue tropism of the viruses was shown to be dependent on the origin of the HN protein. The chimeric virus with the HN protein derived from the virulent virus exhibited a tissue predilection similar to that of the virulent virus, and vice versa. The chimeric viruses with reciprocal HN proteins either gained or lost virulence, as determined by a standard intracerebral pathogenicity index test of chickens and by the mean death time in chicken embryos (a measure devised to classify these viruses), indicating that virulence is a function of the amino acid differences in the HN protein. These results are consistent with the hypothesis that the virulence of NDV is multigenic and that the cleavability of F protein alone does not determine the virulence of a strain.
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Panda A, Huang Z, Elankumaran S, Rockemann DD, Samal SK. Role of fusion protein cleavage site in the virulence of Newcastle disease virus. Microb Pathog 2004; 36:1-10. [PMID: 14643634 PMCID: PMC7125746 DOI: 10.1016/j.micpath.2003.07.003] [Citation(s) in RCA: 224] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Newcastle disease virus (NDV) causes a highly contagious and economically important disease in poultry. Viral determinants of NDV virulence are not completely understood. The amino acid sequence at the protease cleavage site of the fusion (F) protein has been postulated as a major determinant of NDV virulence. In this study, we have examined the role of F protein cleavage site sequence in NDV virulence using reverse genetics technology. The sequence G-R-Q-G-R present at the cleavage site of the F protein of avirulent strain LaSota was mutated to R-R-Q-K-R, which is present in the F cleavage site of neurovirulent strain Beaudette C (BC). The resultant mutated LaSota V.F. virus did not require exogenous protease for infectivity in cell culture, indicating that the F protein was cleaved by intracellular proteases. The virulence of the mutant and parental viruses was evaluated in vivo by intracerebral pathogenicity index (ICPI) and intravenous pathogenicity index (IVPI) tests in chickens. Our results showed that the modification of the F protein cleavage site resulted in a dramatic increase in virulence from an ICPI value of 0.00 for LaSota to a value of 1.12 for LaSota V.F. However, the ICPI value of LaSota V.F. was lower than that of BC, which had a value of 1.58. Interestingly, the IVPI tests showed values of 0.00 for both LaSota and LaSota V.F. viruses, compared to the IVPI value of 1.45 of BC. In vitro characteristics of the viruses were also studied. Our results demonstrate that the efficiency of cleavage of the F protein plays an important role if the NDV is delivered directly into the brains of chicks, but there could be other viral factors that probably affect peripheral replication, viremia, or entry into the central nervous system.
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Subramanian BM, Raj GD, Kumanan K, Nachimuthu K, Nainar AM. Interaction between genomes of infectious bronchitis and Newcastle disease viruses studied by reverse transcription-polymerase chain reaction. Acta Virol 2004; 48:123-9. [PMID: 15462288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Reverse transcription-polymerase chain reaction (RT-PCR) with specific primers for the S1 gene of IBV and for the fusion protein cleavage site of NDV was used for detection of Infectious bronchitis virus (IBV, the family Coronaviridae) and Newcastle disease virus (NDV) genomes. The sensitivity of IBV and NDV RT-PCR was 10(3.7) and 10(3.0) EID50, respectively. Although a multiplex RT-PCR could detect and differentiate NDV and IBV genomes present in the same sample, there was a slight inhibition of the IBV PCR if a high amount of NDV genome was present in the sample. To overcome this problem a separate PCR for each virus was used to assess the interaction between vaccine IBV and NDV either inoculated singly or together into chickens. In the group vaccinated with the Newcastle disease (ND) vaccine alone, the viral genome was detected on days 2, 4 and 7 post vaccination (p.v.), while in the chickens given the infectious bronchitis (IB) vaccine alone, the viral genome was detected only on day 4 p.v. In the group inoculated with both vaccine viruses there was a 10(3)-fold reduction in the cDNA dilution factor on day 4 p.v. for both IBV and NDV genomes. This demonstrated clearly that when both these vaccines are administered there is a transient reduction in the replication of both viruses, probably due to their competition for the same target epithelial cells in the respiratory tract.
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Abstract
The activation of most paramyxovirus fusion proteins (F proteins) requires not only cleavage of F(0) to F(1) and F(2) but also coexpression of the homologous attachment protein, hemagglutinin-neuraminidase (HN) or hemagglutinin (H). The type specificity requirement for HN or H protein coexpression strongly suggests that an interaction between HN and F proteins is required for fusion, and studies of chimeric HN proteins have implicated the membrane-proximal ectodomain in this interaction. Using biotin-labeled peptides with sequences of the Newcastle disease virus (NDV) F protein heptad repeat 2 (HR2) domain, we detected a specific interaction with amino acids 124 to 152 from the NDV HN protein. Biotin-labeled HR2 peptides bound to glutathione S-transferase (GST) fusion proteins containing these HN protein sequences but not to GST or to GST containing HN protein sequences corresponding to amino acids 49 to 118. To verify the functional significance of the interaction, two point mutations in the HN protein gene, I133L and L140A, were made individually by site-specific mutagenesis to produce two mutant proteins. These mutations inhibited the fusion promotion activities of the proteins without significantly affecting their surface expression, attachment activities, or neuraminidase activities. Furthermore, these changes in the sequence of amino acids 124 to 152 in the GST-HN fusion protein that bound HR2 peptides affected the binding of the peptides. These results are consistent with the hypothesis that HN protein binds to the F protein HR2 domain, an interaction important for the fusion promotion activity of the HN protein.
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