Genomic analysis of matrix gene and antigenic studies of its gene product (M1) of a swine influenza virus (H1N1) causing chronic respiratory disease in pigs.
The nucleotide sequence of gene coding for the matrix protein (M1 and M2) of swine influenza (H1N1) virus, A/Sw/Quebec/5393/91 (SwQc91), associated with chronic respiratory disease in pigs, was determined. The deduced amino acid (aa) sequence was compared with the other North American swine strains including the A/Sw/Quebec/192/81 (SwQc81) strain associated with the chronic and acute respiratory disease in pigs. Separate analysis of the M1 and M2 gene products showed different evolutions. M1 had 2 aas changes among 252 aas and these were at positions 4 and 205. The mutation rate was 0.08%, aa changes per residue per year, and its homology with other strains was 99.2%. The M2 protein (97 aas) was relatively more variable than M1 with 5 substitutions. Differences observed were at positions 4, 16, 21, 54 and 95. The mutation rate was 0.51% and its homology with other strains was 94.8%. The M1 gene was cloned in the procaryotic plasmid pET21a and the recombinant plasmid was expressed in Escherichia coli under pre-determined optimal conditions. The recombinant M1 protein (RM1P) (approximately 28 kDa) comigrated as a single band on SDS-PAGE. RM1P was antigenic and reacted with polyclonal sera and 5 monoclonal antibodies (MAbs) spanning 4 epitopes including the membrane binding site and the transcription inhibition activity site. RM1P was immunogenic. The mouse anti-RM1P ELISA antibodies reacted with the purified viral M1 protein and the whole virus.
Welman
M
M
Center de Recherche en Microbiologie et en Biotechnologie, INRS-Institut Armand-Frappier, Université du Quebec, Laval, Canada.
Arora
D J
DJ
D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000235:genetics* / Q000276:immunology; D015153:Blotting, Western / Q000379:methods; D002908:Chronic Disease; D005260:Female; D015870:Gene Expression; D016679:Genome, Viral; D007114:Immunization; D053118:Influenza A Virus, H1N1 Subtype; D009980:Influenza A virus / Q000145:classification / Q000235:genetics* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012141:Respiratory Tract Infections / Q000662:veterinary* / Q000821:virology; D013552:Swine; D013553:Swine Diseases / Q000821:virology*; D014763:Viral Matrix Proteins / Q000235:genetics* / Q000276:immunology; D000086082:Viroporin Proteins
D000956:Antigens, Viral; D011993:Recombinant Fusion Proteins; D014763:Viral Matrix Proteins; C031540:M-protein, influenza virus; C488936:M1 protein, Influenza A virus; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins