Complete Genome Sequence of Avian Paramyxovirus (APMV) Serotype 5 Completes the Analysis of Nine APMV Serotypes and Reveals the Longest APMV Genome

• Published in: PloS one Vol. 5; no. 2; p. e9269
• Main Authors: Samuel, Arthur S, Paldurai, Anandan, Kumar, Sachin, Collins, Peter L, Samal, Siba K
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17.02.2010; Public Library of Science (PLoS)
• Subjects: Amino Acid Sequence; Analysis; Animals; Avian paramyxovirus 5; Avulavirus - classification; Avulavirus - genetics; Base Sequence; Cell lines; Chick Embryo; Chickens; Chickens - virology; Chicks; Chromosome Mapping; Cleavage; Conserved sequence; Cultures; Divergence; Eggs; Eggs (Food); Epidemiology; F protein; Furin; Gene sequencing; Genes; Genetic aspects; genome; Genome, Viral - genetics; Genomes; Genomics; Hemagglutinins; Infections; Infectious diseases; Juveniles; Laboratories; Lectins; Measles; Molecular Sequence Data; Mortality; Nucleotide sequence; nucleotide sequences; Nucleotides; Pathogenicity; Pathogens; Phylogeny; Poultry; Protease; Proteases; Protein expression; Proteinase; Proteins; Respiratory syncytial virus; Reverse Transcriptase Polymerase Chain Reaction; Ribonucleic acid; RNA; RNA editing; RNA, Viral - genetics; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Sequence Homology, Nucleic Acid; Serotypes; Serotyping; Veterinary colleges; Veterinary medicine; Viral Proteins - genetics; Virions; Virology; Virology/Animal Models of Infection; Virology/Virus Evolution and Symbiosis; Virulence; Virus replication; Viruses; United States > US; Maryland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0009269

Background: Avian paramyxoviruses (APMV) consist of nine known serotypes. The genomes of representatives of all APMV serotypes except APMV type 5 have recently been fully sequenced. Here, we report the complete genome sequence of the APMV-5 prototype strain budgerigar/Kunitachi/74. Methodology/Principal Findings: APMV-5 Kunitachi virus is unusual in that it lacks a virion hemagglutinin and does not grow in the allantoic cavity of embryonated chicken eggs. However, the virus grew in the amniotic cavity of embryonated chicken eggs and in twelve different established cell lines and two primary cell cultures. The genome is 17,262 nucleotides (nt) long, which is the longest among members of genus Avulavirus, and encodes six non-overlapping genes in the order of 3′N-P/V/W-M-F-HN-L-5′ with intergenic regions of 4–57 nt. The genome length follows the ‘rule of six’ and contains a 55-nt leader sequence at the 3′end and a 552 nt trailer sequence at the 5′ end. The phosphoprotein (P) gene contains a conserved RNA editing site and is predicted to encode P, V, and W proteins. The cleavage site of the F protein (G-K-R-K-K-R↓F) conforms to the cleavage site motif of the ubiquitous cellular protease furin. Consistent with this, exogenous protease was not required for virus replication in vitro. However, the intracerebral pathogenicity index of APMV-5 strain Kunitachi in one-day-old chicks was found to be zero, indicating that the virus is avirulent for chickens despite the presence of a polybasic F cleavage site. Conclusions/Significance: Phylogenetic analysis of the sequences of the APVM-5 genome and proteins versus those of the other APMV serotypes showed that APMV-5 is more closely related to APMV-6 than to the other APMVs. Furthermore, these comparisons provided evidence of extensive genome-wide divergence that supports the classification of the APMVs into nine separate serotypes. The structure of the F cleavage site does not appear to be a reliable indicator of virulence among APMV serotypes 2–9. The availability of sequence information for all known APMV serotypes will facilitate studies in epidemiology and vaccinology.