Polyprotein processing in African swine fever virus: a novel gene expression strategy for a DNA virus.
This report shows that African swine fever virus (ASFV)--a large DNA-containing virus--synthesizes a polyprotein to produce several of its structural proteins. By immunoprecipitation analysis, we have found that ASFV polyprotein is a 220 kDa myristoylated polypeptide (pp220) which, after proteolytic processing, gives rise to four major structural proteins: p150, p37, p34 and p14. Processing of the ASFV polyprotein takes place at the consensus sequence Gly-Gly-X and occurs through an ordered cascade of proteolytic cleavages. So far, polyprotein processing as a mechanism of gene expression had been found only in positive-strand RNA viruses and retroviruses. According to the results presented here, ASFV is the first example of a DNA virus that synthesizes a polyprotein as a strategy of gene expression.
Simón-Mateo
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C
Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Facultad de Ciencias, Universidad Autónoma, Madrid, Spain.
Andrés
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G
Viñuela
E
E
D000358:African Swine Fever Virus / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D004274:DNA, Recombinant; D015967:Gene Expression Regulation, Viral; D016679:Genome, Viral; D006868:Hydrolysis; D008969:Molecular Sequence Data; D009024:Morphogenesis; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D014709:Vero Cells; D015678:Viral Structural Proteins / Q000235:genetics / Q000378:metabolism*
D004274:DNA, Recombinant; D009227:Myristic Acids; D011506:Proteins; D015678:Viral Structural Proteins; D019814:Myristic Acid