• 한국양식학회:학술대회논문집
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• 한국양식학회 2006년도 수산관련학회 공동학술대회 발표요지집
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• pp.476-478
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• 2006

To analyze subcellular localization of betanodavirus protein B2, a plasmid expressing Betanodavirus protein B2 fused to enhanced green fluorescent protein (EGFP-Nl) was constructed. The transient expression of full-length B2 fused to EGFP in GF cells confirmed the equal distribution of protein B2 between cytoplasm and nucleus. However, transfection of N-terminal half of the B2 revealed that this truncated form predominantly localized to the cytoplasm. By using several deletion mutants and point mutants, we determined the regions and/or motif responsible for the subcellular localization of betanodavirus.

• 한국어병학회지
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• 제34권2호
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• pp.133-140
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• 2021

With the recent isolation of a new betanodavirus in shellfish, Korean Shellfish Nervous Necrosis Virus (KSNNV), it has also been identified the reassortant KSNNV of two RNA segments, in which one segment is KSNNV genotype but the other one is known genotype. In this study, we confirmed that the ressortant KSNNVs obtained in previous screening study of our laboratory for betanodaviruses in shellfish were KS/RGNNV and RG/KSNNV type by performing two consecutive multiplex RT-PCR on each RNA1 and RNA2 segment (R1- and R2-discriminative multiplex two-step RT-PCR, respectively) to determine the genotype of each segment based on the size of amplicon. In the pathogenicity analysis, none of the reassortants induced specific external symptoms or mortality of VNN, but viruses of 2 × 10⁴~10⁵ copies/mg or more were detected at 14 days after injection (10⁷ copies/fish) in brain tissues of 4 species except for crucian carp and common carp among the 6 species of juvenile fish used. In addition, the histopathological features of weak but distinct vacuole formation were also found in the brain of these infected fish, but no difference was found between the two reassortants KS/RGNNV-KG and RG/KSNNV-CM.

• 한국해양바이오학회지
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• 제2권3호
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• pp.127-132
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• 2007

The innate immune response which is seen as the initial defense mechanism induced upon foreign invasion has been well documented in higher vertebrates. This has also been observed in fish infected with NNV. However, the fish immune system based on fully established genome project has not been fully elucidated. Therefore, in this review, we hope to correlate NNV infection in fish that has devastated the aquaculture industry, to its host immune system. Further, we discuss the potential preventive measures in overcoming the widespread of this neurodisease.

• 한국어류학회지
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• 제29권3호
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• pp.157-164
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• 2017

2015년 겨울, 우리나라 남해안 소재 육상 양식장에서 사육 중이던 능성어의 약 30%가 폐사하였다. 수온 $9{\sim}12^{\circ}C$의 겨울철에 발생한 능성어 폐사는 신경괴사성바이러스 (NNV) 감염에 의한 바이러스성뇌망망증 (VER)으로 밝혀졌다. 시험어는 비정상적인 유영, 배를 위로한 채 수면을 떠 다니는 현상, 체색흑화, 안구백탁 및 부레의 과도한 팽창 소견을 보였다. 원인 바이러스는 일반적으로 고수온기 능성어에 감염되는 RGNNV genotype이 아닌, 냉수성 어류에서 분리되는 BFNNV genotype으로 밝혀졌으며, NNV 가장 근연관계가 높은 Pacific cod betanodavirus (PCNNV)와 99.7~100% 상동성을 보였다. 병리조직학적 관찰 결과, 바이러스성뇌망망증 (VER)의 특징적인 병변인 뇌조직의 공포화 및 괴사를 수반하였다. 이 연구는 수온 $12^{\circ}C$ 이하의 겨울철에 능성어에 감염된 BFNNV genotype에 대한 첫 보고이다.

• 한국어병학회지
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• 제22권3호
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• pp.219-228
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• 2009

The genomic and subgenomic RNAs of fish nodavirus encode the four proteins, protein A, capsid protein, non-structural protein B1 and B2. In this study, we describe the immune response of olive flounder Paralichthys olivaceus immunized with live fish nodavirus or recombinant capsid protein, non-structural protein B1 and B2 expressed in E. coli. Nodavirus-infected flounder produced antibodies to capsid protein, B1 and B2 and nodavirus-neutralizing activities were detected in the serum of the nodavirus-infected flounder. The flounder were immunized against the three recombinant proteins of fish nodavirus and the sera from these immunized fishes were assayed for nodavirus-specific antibody by ELISA and a neutralization test. In the immunized flounder, all three recombinant proteins induced the production of similar levels of antibody, but only the antibody to capsid protein significantly neutralized nodavirus. These results indicate that all three nodaviral proteins are immunogenic in flounder, but only the capsid protein can induce neutralizing antibody against nodavirus.