Phylogenetic analysis of betanodaviruses isolated from cultured fish in Korea

Abstract

Since the publication of the first report on fish nodaviruses in Korea in 1998(Sohn et al. 1998 J Fish Pathol 11:97-104), fish nodaviruses have caused widespread epizootic events among various fish species in Korea. However, the genotypes of fish nodaviruses in Korea have not yet been determined due to a lack of information about their nucleotide sequences. In this study, we isolated 5 fish nodaviruses from 4 fish species cultured in 4 different regions in Korea: rock bream Oplegnathus fasciatus, Japanese flounder Paralichthys olivaceus, sevenband grouper Epinephelus septemfasciatus, and grey mullet Mugil cephalus. The full open-reading frame (ORF) encoding the coat protein (1017 nt) was sequenced from each of the 5 fish nodaviruses and the nucleotide sequences were phylogenetically analyzed. Results showed that even though their sequences were not identical, all 5 Korean isolates were clustered in the RGNNV genotype. This is the first report on the phylogenetic analysis of fish nodaviruses from cultured fish in Korea. KEY WORDS: Fish nodavirus · Coat protein · Phylogenetic analysisResale or republication not permitted without written consent of the publisher

Betanodavirus of Marine and Freshwater Fish: Distribution, Genomic Organization, Diagnosis and Control Measures

“…However, the genome arrangement of the virus can vary from strain to strain. To substantiate and understand this, phylogenetic analysis was carried out based on the gene encoding viral coat protein for various viral strains [16,45,90,91]. For example, the sequence similarities among SJNNV and the coat protein gene from different fish VNN viruses was found to be 75.8 % or greater at the nucleotide level and 80.9 % or greater at the amino-acid level [90].…”

“…Analysis also suggest that strain variation of the virus is not related to the hostdependent evolution and/or geography. Betanodavirus appear to adapt easily to other fish species [16].…”

Characterization of the Transcriptome and Gene Expression of Brain Tissue in Sevenband Grouper (Hyporthodus septemfasciatus) in Response to NNV Infection

“…The infected fish are usually swimming abnormally and having vacuolization and necrosis of the central nervous system in the brain [ 3 ]. In Korea, mass mortalities caused by VNN have been reported from various cultured marine fish such as sevenband grouper ( Hyporthodus septemfasciatus ), rock bream ( Oplegnathus fasciatus ), red drum ( Sciaenops ocellatus ) and olive flounder ( Paralichthys olivaceus ) since 1990 [ 5 , 6 , 7 ].…”

Isolation and Infectious Temperature Optimization of Genetically Similar VHSV Isolates in Farmed Olive Flounder, Paralichthys olivaceus

“…Genetically similar VHSV isolates from flounder farms in the southern part of Korea revealed greater pathogenicity than the Jeju isolates (Cho et al, 2012). Other fish viruses from flounder farms in Korea include infectious hematopoietic necrosis virus (IHNV; Park et al, 1993;Kim et al, 2007), infectious hematopoietic necrosis virus (HIRRV; Kim et al, 2005), marine birna virus (Sohn et al, 1995), beta nodavirus (Cha et al, 2007), and iridovirus (Do et al, 2005).…”