Hemagglutinin activation of pathogenic avian influenza viruses of serotype H7 requires the protease recognition motif R-X-K/R-R.
The hemagglutinin of influenza virus A/FPV/Rostock/34 (H7) was altered at its multibasic cleavage site by site-directed mutagenesis and assayed for proteolytic activation after expression in CV-1 cells. The results indicated that the cellular protease responsible for activation recognizes the tetrapeptide motif R-X-K/R-R that must be presented in the correct sequence position. Studies on plaque variants of influenza virus A/fowl/Victoria/75 (H7N7) showed that alteration of the consensus sequence resulted in a loss of pathogenicity for chickens.
Vey
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M
Institut für Virologie, Philipps-Universität Marburg, Germany.
Orlich
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Adler
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Klenk
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Rott
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Garten
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D000595:Amino Acid Sequence; D001483:Base Sequence; D004279:DNA, Viral; D010450:Endopeptidases / Q000378:metabolism*; D006389:Hemagglutinins, Viral / Q000378:metabolism*; D009980:Influenza A virus / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011392:Proline / Q000378:metabolism
D004279:DNA, Viral; D006389:Hemagglutinins, Viral; D011392:Proline; D010450:Endopeptidases