Genetic variation in V gene of class II Newcastle disease virus

The genetic variation and molecular evolution of the V gene of the class II Newcastle disease virus (NDV) isolates with genotypes I-XVIII were determined using bioinformatics. Results indicated that low homology existed in different genotype viruses, whereas high homology often for the same genotypes, exception may be existed within genotypes I, V, VI, and XII. Sequence analysis showed that the genetic variation of V protein was consistent with virus genotype, and specific signatures on the V protein for nine genotypes were identified. Phylogenetic analysis demonstrated that the phylogenetic trees were highly consistent between the V and F genes, with slight discrepancies in the sub-genotypes. Evolutionary rate analyses based on V and F genes revealed the evolution rates varied in genotypes. These data indicate that the genetic variation of V protein is genotype-related and will help in elucidating the molecular evolution of NDV.