Adelaide River virus nucleoprotein gene: analysis of phylogenetic relationships of ephemeroviruses and other rhabdoviruses.

The nucleotide sequence of the Adelaide River virus (ARV) genome was determined from the 3' terminus to the end of the nucleoprotein (N) gene. The 3' leader sequence comprises 50 nucleotides and shares a common terminal trinucleotide (3' UGC-), a conserved U-rich domain and a variable AU-rich domain with other animal rhabdoviruses. The N gene comprises 1355 nucleotides from the transcription start sequence (AACAGG) to the poly(A) sequence [CATG(A)7] and encodes a polypeptide of 429 amino acids. The N protein has a calculated molecular mass of 49429 Da and a pI of 5.4 and, like the bovine ephemeral fever virus (BEFV) N protein, features a highly acidic C-terminal domain. Analysis of amino acid sequence relationships between all available rhabdovirus N proteins indicated that ARV and BEFV are closely related viruses (48.3% similarity) which share higher sequence similarity to vesiculoviruses than to lyssaviruses. Phylogenetic trees based on a multiple sequence alignment of all available rhabdovirus N protein sequences demonstrated clustering of viruses according to genome organization, host range and established taxonomic relationships.