An African swine fever virus ERV1-ALR homologue, 9GL, affects virion maturation and viral growth in macrophages and viral virulence in swine.
The African swine fever virus (ASFV) genome contains a gene, 9GL, with similarity to yeast ERV1 and ALR genes. ERV1 has been shown to function in oxidative phosphorylation and in cell growth, while ALR has hepatotrophic activity. 9GL encodes a protein of 119 amino acids and was highly conserved at both nucleotide and amino acid levels among all ASFV field isolates examined. Monospecific rabbit polyclonal antibody produced to a glutathione S-transferase-9GL fusion protein specifically immunoprecipitated a 14-kDa protein from macrophage cell cultures infected with the ASFV isolate Malawi Lil-20/1 (MAL). Time course analysis and viral DNA synthesis inhibitor experiments indicated that p14 was a late viral protein. A 9GL gene deletion mutant of MAL (Delta9GL), exhibited a growth defect in macrophages of approximately 2 log(10) units and had a small-plaque phenotype compared to either a revertant (9GL-R) or the parental virus. 9GL affected normal virion maturation; virions containing acentric nucleoid structures comprised 90 to 99% of all virions observed in Delta9GL-infected macrophages. The Delta9GL virus was markedly attenuated in swine. In contrast to 9GL-R infection, where mortality was 100%, all Delta9GL-infected animals survived infection. With the exception of a transient fever response in some animals, Delta9GL-infected animals remained clinically normal and exhibited significant 100- to 10,000-fold reductions in viremia titers. All pigs previously infected with Delta9GL survived infection when subsequently challenged with a lethal dose of virulent parental MAL. Thus, ASFV 9GL gene deletion mutants may prove useful as live-attenuated ASF vaccines.
Lewis
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Plum Island Animal Disease Center, Agricultural Research Service, U. S. Department of Agriculture, Greenport, New York 11944-0848, USA.
Zsak
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Burrage
T G
TG
Lu
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Kutish
G F
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Neilan
J G
JG
Rock
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DL
D000357:African Swine Fever / Q000276:immunology / Q000821:virology*; D000358:African Swine Fever Virus / Q000235:genetics / Q000254:growth & development* / Q000276:immunology / Q000472:pathogenicity*; D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics; D017353:Gene Deletion; D007114:Immunization; D008264:Macrophages / Q000648:ultrastructure / Q000821:virology*; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D009363:Neoplasm Proteins; D050862:Oxidoreductases Acting on Sulfur Group Donors; D051381:Rats; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D013552:Swine; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D014764:Viral Proteins / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D014771:Virion / Q000254:growth & development; D014774:Virulence
C403418:9GL protein, African swine fever virus; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C120898:KMT2D protein, human; D024101:Mitochondrial Proteins; D009363:Neoplasm Proteins; D029701:Saccharomyces cerevisiae Proteins; D017361:Viral Nonstructural Proteins; D014764:Viral Proteins; D050862:Oxidoreductases Acting on Sulfur Group Donors; C073790:ERV1 protein, S cerevisiae