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Avian paramyxovirus serotype-1: a review of disease distribution, clinical symptoms, and laboratory diagnostics.

Hines NL, Miller CL - Vet Med Int (2012)

Bottom Line: Avian paramyxovirus serotype-1 (APMV-1) is capable of infecting a wide range of avian species leading to a broad range of clinical symptoms.Classification systems have been designed to group isolates based on their genetic composition.Genetic diversity within APMV-1 demonstrates the need for continual monitoring for changes that may arise requiring modifications to the molecular assays to maintain their usefulness for diagnostic testing.

View Article: PubMed Central - PubMed

Affiliation: National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, United States Department of Agriculture, Ames, IA 50010, USA.

ABSTRACT
Avian paramyxovirus serotype-1 (APMV-1) is capable of infecting a wide range of avian species leading to a broad range of clinical symptoms. Ease of transmission has allowed the virus to spread worldwide with varying degrees of virulence depending on the virus strain and host species. Classification systems have been designed to group isolates based on their genetic composition. The genetic composition of the fusion gene cleavage site plays an important role in virulence. Presence of multiple basic amino acids at the cleavage site allows enzymatic cleavage of the fusion protein enabling virulent viruses to spread systemically. Diagnostic tests, including virus isolation, real-time reverse-transcription PCR, and sequencing, are used to characterize the virus and identify virulent strains. Genetic diversity within APMV-1 demonstrates the need for continual monitoring for changes that may arise requiring modifications to the molecular assays to maintain their usefulness for diagnostic testing.

No MeSH data available.


Related in: MedlinePlus

(a) The prefusion form of F contains a globular head with the HRA region in 11 distinct sections, and the HRB region is in a three-helix bundle. The F TM domain is also represented as a three-helix bundle, consistent with the oxidative cross-linking data. (b) Upon HN binding to target cells (HN not shown for clarity), F is activated for fusion, and the HRB region separates, forming the open-stalk conformation where N-1 peptide can bind to HRB. At this open-stalk stage, the TM domain is still thought to be in a three-helix bundle because N-1-HAt can still bind to HRB after the addition of the oxidative cross-linker. (c) After formation of the open-stalk conformation, HRA rearranges to form the extended α-helical bundle, and the FP is inserted into the target cell membrane (the prehairpin intermediate). (d-e) Finally, the postfusion state occurs with the formation of the 6-HB. (d-e and f–i) Lipid intermediates in fusion with the F protein, removed for clarity. The two bilayers contain an inner and outer leaflets and are separated by the extracellular space. During the process of F refolding to form the postfusion form, water is excluded from the extracellular space and the outer leaflets initially merge to form the lipid stalk intermediate. The lipids of the bilayers mix, forming the hemifusion intermediate, and then the fusion pore forms. F domains: FP (red), HRA (green), globular head (yellow), HRB (blue), TM domain (orange), cytoplasmic tail (pink). (From Bissonnette et al., 2009 [44] with permission.)
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fig1: (a) The prefusion form of F contains a globular head with the HRA region in 11 distinct sections, and the HRB region is in a three-helix bundle. The F TM domain is also represented as a three-helix bundle, consistent with the oxidative cross-linking data. (b) Upon HN binding to target cells (HN not shown for clarity), F is activated for fusion, and the HRB region separates, forming the open-stalk conformation where N-1 peptide can bind to HRB. At this open-stalk stage, the TM domain is still thought to be in a three-helix bundle because N-1-HAt can still bind to HRB after the addition of the oxidative cross-linker. (c) After formation of the open-stalk conformation, HRA rearranges to form the extended α-helical bundle, and the FP is inserted into the target cell membrane (the prehairpin intermediate). (d-e) Finally, the postfusion state occurs with the formation of the 6-HB. (d-e and f–i) Lipid intermediates in fusion with the F protein, removed for clarity. The two bilayers contain an inner and outer leaflets and are separated by the extracellular space. During the process of F refolding to form the postfusion form, water is excluded from the extracellular space and the outer leaflets initially merge to form the lipid stalk intermediate. The lipids of the bilayers mix, forming the hemifusion intermediate, and then the fusion pore forms. F domains: FP (red), HRA (green), globular head (yellow), HRB (blue), TM domain (orange), cytoplasmic tail (pink). (From Bissonnette et al., 2009 [44] with permission.)

Mentions: Replication of NDV begins by attachment of the virus to the host cell membrane. The HN protein binds to the SA receptors on the surface of the cell membrane bringing the F protein closer to the host cell [42, 44, 45]. The HN interaction with SA receptors is thought to initiate the conformational changes needed to activate the F protein. Figure 1 is a model provided by Bissonnette et al., describing membrane fusion events [44]. During fusion events the F1 polypeptide undergoes additional conformational changes which expose the HRA and HRB regions [42, 44]. The two hydrophobic regions of the F1 polypeptide act to bind the viral membrane to the host cell membrane. The N-terminal fusion peptide attaches to the host cell membrane, while the transmembrane domain anchors the viral membrane. A 6-helix bundle (6HB) couples the free energy released during protein refolding when the two membranes merge. The final conformational state of the F protein is the most stable form and is not reversible [44].


Avian paramyxovirus serotype-1: a review of disease distribution, clinical symptoms, and laboratory diagnostics.

Hines NL, Miller CL - Vet Med Int (2012)

(a) The prefusion form of F contains a globular head with the HRA region in 11 distinct sections, and the HRB region is in a three-helix bundle. The F TM domain is also represented as a three-helix bundle, consistent with the oxidative cross-linking data. (b) Upon HN binding to target cells (HN not shown for clarity), F is activated for fusion, and the HRB region separates, forming the open-stalk conformation where N-1 peptide can bind to HRB. At this open-stalk stage, the TM domain is still thought to be in a three-helix bundle because N-1-HAt can still bind to HRB after the addition of the oxidative cross-linker. (c) After formation of the open-stalk conformation, HRA rearranges to form the extended α-helical bundle, and the FP is inserted into the target cell membrane (the prehairpin intermediate). (d-e) Finally, the postfusion state occurs with the formation of the 6-HB. (d-e and f–i) Lipid intermediates in fusion with the F protein, removed for clarity. The two bilayers contain an inner and outer leaflets and are separated by the extracellular space. During the process of F refolding to form the postfusion form, water is excluded from the extracellular space and the outer leaflets initially merge to form the lipid stalk intermediate. The lipids of the bilayers mix, forming the hemifusion intermediate, and then the fusion pore forms. F domains: FP (red), HRA (green), globular head (yellow), HRB (blue), TM domain (orange), cytoplasmic tail (pink). (From Bissonnette et al., 2009 [44] with permission.)
© Copyright Policy - open-access
Related In: Results  -  Collection

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fig1: (a) The prefusion form of F contains a globular head with the HRA region in 11 distinct sections, and the HRB region is in a three-helix bundle. The F TM domain is also represented as a three-helix bundle, consistent with the oxidative cross-linking data. (b) Upon HN binding to target cells (HN not shown for clarity), F is activated for fusion, and the HRB region separates, forming the open-stalk conformation where N-1 peptide can bind to HRB. At this open-stalk stage, the TM domain is still thought to be in a three-helix bundle because N-1-HAt can still bind to HRB after the addition of the oxidative cross-linker. (c) After formation of the open-stalk conformation, HRA rearranges to form the extended α-helical bundle, and the FP is inserted into the target cell membrane (the prehairpin intermediate). (d-e) Finally, the postfusion state occurs with the formation of the 6-HB. (d-e and f–i) Lipid intermediates in fusion with the F protein, removed for clarity. The two bilayers contain an inner and outer leaflets and are separated by the extracellular space. During the process of F refolding to form the postfusion form, water is excluded from the extracellular space and the outer leaflets initially merge to form the lipid stalk intermediate. The lipids of the bilayers mix, forming the hemifusion intermediate, and then the fusion pore forms. F domains: FP (red), HRA (green), globular head (yellow), HRB (blue), TM domain (orange), cytoplasmic tail (pink). (From Bissonnette et al., 2009 [44] with permission.)
Mentions: Replication of NDV begins by attachment of the virus to the host cell membrane. The HN protein binds to the SA receptors on the surface of the cell membrane bringing the F protein closer to the host cell [42, 44, 45]. The HN interaction with SA receptors is thought to initiate the conformational changes needed to activate the F protein. Figure 1 is a model provided by Bissonnette et al., describing membrane fusion events [44]. During fusion events the F1 polypeptide undergoes additional conformational changes which expose the HRA and HRB regions [42, 44]. The two hydrophobic regions of the F1 polypeptide act to bind the viral membrane to the host cell membrane. The N-terminal fusion peptide attaches to the host cell membrane, while the transmembrane domain anchors the viral membrane. A 6-helix bundle (6HB) couples the free energy released during protein refolding when the two membranes merge. The final conformational state of the F protein is the most stable form and is not reversible [44].

Bottom Line: Avian paramyxovirus serotype-1 (APMV-1) is capable of infecting a wide range of avian species leading to a broad range of clinical symptoms.Classification systems have been designed to group isolates based on their genetic composition.Genetic diversity within APMV-1 demonstrates the need for continual monitoring for changes that may arise requiring modifications to the molecular assays to maintain their usefulness for diagnostic testing.

View Article: PubMed Central - PubMed

Affiliation: National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, United States Department of Agriculture, Ames, IA 50010, USA.

ABSTRACT
Avian paramyxovirus serotype-1 (APMV-1) is capable of infecting a wide range of avian species leading to a broad range of clinical symptoms. Ease of transmission has allowed the virus to spread worldwide with varying degrees of virulence depending on the virus strain and host species. Classification systems have been designed to group isolates based on their genetic composition. The genetic composition of the fusion gene cleavage site plays an important role in virulence. Presence of multiple basic amino acids at the cleavage site allows enzymatic cleavage of the fusion protein enabling virulent viruses to spread systemically. Diagnostic tests, including virus isolation, real-time reverse-transcription PCR, and sequencing, are used to characterize the virus and identify virulent strains. Genetic diversity within APMV-1 demonstrates the need for continual monitoring for changes that may arise requiring modifications to the molecular assays to maintain their usefulness for diagnostic testing.

No MeSH data available.


Related in: MedlinePlus