Molecular and phylogenetic analyses of the haemagglutinin (H) proteins of field isolates of canine distemper virus from naturally infected dogs.
We isolated three strains of canine distemper virus (CDV)--the Ueno, Hamamatsu, and Yanaka strains--from dogs in Japan and analysed the molecular properties of their haemagglutinin (H) proteins. Immunoprecipitation of all three strains with a monoclonal antibody revealed H proteins with molecular masses of 84 kDa, which differs from the molecular mass (78 kDa) of the H protein of the Onderstepoort vaccine strain. However, after tunicamycin treatment immunoprecipitation identified H proteins of identical molecular mass (68 kDa) for all three field isolates and the vaccine strain. Sequence analysis showed nine potential sites for asparagine-linked glycosylation in the H proteins of the new isolates, in contrast to four in the H protein of the Onderstepoort strain. Thus, variation in glycosylation of the H proteins of the isolates and the vaccine strain may cause differences in antigenicity of the viruses. Sequences of the H genes showed that the new Japanese isolates have 99% identity with each other, 95% with other European and American isolates (from seals, a German dog, a ferret and large felids) and 90% with the vaccine strain. Phylogenetically, the new Japanese isolates form one cluster which is separate from recent European or American isolates, all of which are distinct from vaccine strains.
Iwatsuki
K
K
Department of Veterinary Microbiology, Faculty of Agriculture, The University of Tokyo, Bunkyo-ku, Japan.
Miyashita
N
N
Yoshida
E
E
Gemma
T
T
Shin
Y S
YS
Mori
T
T
Hirayama
N
N
Kai
C
C
Mikami
T
T
D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000145:classification / Q000235:genetics / Q000276:immunology; D002460:Cell Line; D018920:Coculture Techniques; D004216:Distemper / Q000821:virology*; D004217:Distemper Virus, Canine / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D004285:Dogs; D006023:Glycoproteins / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010802:Phylogeny; D016415:Sequence Alignment; D014764:Viral Proteins / Q000145:classification / Q000235:genetics*; D014765:Viral Vaccines / Q000145:classification / Q000235:genetics / Q000276:immunology
D000956:Antigens, Viral; D006023:Glycoproteins; D014764:Viral Proteins; D014765:Viral Vaccines