Molecular assembly of influenza virus: association of the NS2 protein with virion matrix.
The NS2 protein, one of the two nonstructural proteins of influenza A virus, was found to exist in virus particles. By immunochemical method, the average number of NS2 in a virus particle was estimated to be 130-200 molecules. After solubilization of viral envelope, NS2 was still associated with ribonucleoprotein cores, but was later dissociated upon removal of the M1 protein. A filter-binding assay in vitro indicated direct protein-protein contact between M1 and NS2. Following chemical cleavage of the M1 protein, NS2 bound only a C-terminal fragment of M1. By immunoprecipitation, NS2-M1 complexes were also detected in virus-infected cell lysates. These observations altogether indicate specific molecular association between M1 and NS2. Biological significance of M1-NS2 interaction is discussed.
Yasuda
J
J
Department of Molecular Genetics, National Institute of Genetics, Shizuoka, Japan.
Nakada
S
S
Kato
A
A
Toyoda
T
T
Ishihama
A
A
D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D002478:Cells, Cultured; D002642:Chick Embryo; D004285:Dogs; D015151:Immunoblotting; D009980:Influenza A virus / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000378:metabolism; D014763:Viral Matrix Proteins / Q000378:metabolism*; D017361:Viral Nonstructural Proteins / Q000032:analysis / Q000378:metabolism*; D014771:Virion / Q000378:metabolism
C031540:M-protein, influenza virus; C488936:M1 protein, Influenza A virus; D012261:Ribonucleoproteins; D014763:Viral Matrix Proteins; D017361:Viral Nonstructural Proteins