Phylogenetic profile of the Akabane virus strains based on the sequence of the M RNA segment. The ORF nucleotide sequences of the M RNA segment (4203 nucleotides) were aligned, and a phylogenetic tree was constructed by the neighbor-joining method. The corresponding nucleotide sequence of Aino virus strain JaNAr28 in the genus Orthobunyavirus was used as an outgroup to root the tree. The percentage bootstrap values calculated from 1000 replications are indicated above the internal nodes. The scale represents the 10% nucleotide sequence divergence. The geographical origin and year of isolation of the strains are given in the parentheses.