Journal of The School of Marine Science and Technology,Vol.1 No.1
Sequence of genome segment A of a birnavirus isolated from cultured Japnanese eel with viral endothelial cell necrosis of eel
Shin-ichi ONO, Kouji WAKABAYASHI and Akira NAGAI
Abstract
A birnavirus (Eel Birnavirus Japanese; EBVJ) has been isolated from cultured Japanese eel (Anguilla japonica)
infected with gill disease characterized by viral endothelial cell necrosis of eel (VECNE)in Japan. The cDNA sequence
(3,041bp) of almost complete region in segment A including the large open reading frame (ORF) from EBVJ was
determined, and compared to the sequences of the other twenty-six strains of birnavirus. The size of the large ORF and
small open reading frame (small ORF) in segment A of EBVJ was 2,916bp and 411bp respectively, and also VP2/NS
junction region was 310bp long. Comparing the segment A nucleotide sequence exhibited that EBVJ had high homology(87.
4% homology) with N1 strain of infectious pancreatic necrosis virus (IPNV). In addition, EBVJ showed the highest
homology with Ab strain of IPNV as comparing nucleotide sequences at VP2 (95.0％ homology) and VP2/NS (96.8％
homology)junction regions. Amino acid sequence of EBVJ was also very similar to Ab strain in VP2/NS junction region.
Analysis of molecular phylogenetic trees among EBVJ and twenty-six strains of birnaviruses revealed that EBVJ was very
close to Ab strain and belonged to genogroupⅡ including Ab, C1, C2, C3, TE2, Sp, N1 and Fr, 21 strains of IPNV.