• Korean Journal of Microbiology
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• v.36 no.2
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• pp.103-108
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• 2000

We have cloned and analyzed cDNA coding for non-virion (NV) protein of the m V - P R T The NV gene contained 336 bp open readmg frame and encoded a protein of 11 1 amino acids with a molecular weight of 13.2 kDa. The deduced amino acid sequence of NV of IHNVPRT was found to be 90-95% identical to those of foreign isolates of IHNV. These results indicate that NV gene of the MNV is highly conserved among &ifferent strains of THNV Northern blot analyses revealed that the levels of NV gene expression were strongly elevated after 20 h post-infection. In order to identify the role of NV in the replication of MNV in fish cells, IHNVinfected cells were treated with antisense oligonucleotides. While IHNV-PRT exposed to glycoprotein (G) antisense oligonucleotide showed severely reduced growth, the growth of virus exposed to NV antisense oligonucleotide was not affected by NV antisense oligonucleotide, which suggests that NV is not essential for replication of IHNV in fish cells.

• Journal of Life Science
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• v.26 no.12
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• pp.1470-1476
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• 2016

The viral hemorrhagic septicemia virus (VHSV), which belongs to the Novirhabdovirus genus of the Rhabdoviridae family, is a viral pathogen that causes severe losses in the olive flounder farming industry. Among six encoding VHSV proteins, the non-virion (NV) protein has been shown to have an impact on virulence. In our previous studies, transcriptomics microarray analysis by using VHSV-infected olive flounder showed that VHSV infection significantly down-regulated the mRNA expression of glycolytic enzymes. In addition, VHSV NV protein variants decreased the intracellular ATP level. Based on these results, we have tried to examine the effect of VHSV NV protein on glycolytic enzyme glucokinase expression, which phosphorylates glucose to glucose 6-phosphate. Our results indicated that the NV protein significantly decreased the mRNA expression of glucokinase in olive flounder HINAE cells. Furthermore, the NV protein played a negative role in the promoter activation of glucokinase. Furthermore, glucose uptake was effectively inhibited by VHSV infection and NV protein expression in olive flounder HINAE cells. These results suggest that the VHSV NV protein negatively regulates glycolytic enzyme expression by a transcription level and eventually leads to gradual morbidity of olive flounder through cellular energy deprivation. The present results may be useful for the prevention and diagnosis of VHSV infection in olive flounder.

• Biomolecules & Therapeutics
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• v.21 no.2
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• pp.97-106
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• 2013

Chronic hepatitis C virus (HCV) infection is responsible for the development of liver cirrhosis and hepatocellular carcinoma. HCV core protein plays not only a structural role in the virion morphogenesis by encapsidating a virus RNA genome but also a non-structural role in HCV-induced pathogenesis by blocking innate immunity. Especially, it has been shown to regulate JAK-STAT signaling pathway through its direct interaction with Janus kinase (JAK) via its proline-rich JAK-binding motif ($^{79}{\underline{P}}GY{\underline{P}}WP^{84}$). However, little is known about the physiological significance of this HCV core-JAK association in the context of the virus life cycle. In order to gain an insight, a mutant HCV genome (J6/JFH1-79A82A) was constructed to express the mutant core with a defective JAK-binding motif ($^{79}{\underline{A}}GY{\underline{A}}WP^{84}$) using an HCV genotype 2a infectious clone (J6/JFH1). When this mutant HCV genome was introduced into hepatocarcinoma cells, it was found to be severely impaired in its ability to produce infectious viruses in spite of its robust RNA genome replication. Taken together, all these results suggest an essential requirement of HCV core-JAK protein interaction for efficient production of infectious viruses and the potential of using core-JAK blockers as a new anti-HCV therapy.

• Journal of Microbiology
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• v.40 no.3
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• pp.183-192
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• 2002

Cells infected With equine herpesvirus type-1 (EHV-1) Produced both infectious and non-infectious Virus-related particles. Compared to the whole virion, non-infectious particles termed L-particles were deter-mined to lack 150 kDa protein, commonly known as nucleocapsid protein. The potential of L-particles to induce immune responses was studied in mice and foals. Intranasal immunization with L-particles or whole virions induced poor IgG antibody responses in mice. Interestingly, despite the poor antibody response, the conferred immunity protected the host from challenge infections. This was indicated by a significant reduction in virus titers in line with recovery towards normal body weight. Subsequently, the test on the usefulness of L-particles as immunizing agents was extended to foals. Immunization of specific-pathogen-free (SPF) foals resulted in similar results. As determined by a complement-fixing-antibody test (CFT), foals seroconverted when they were immunized either with inactivated L-particles or whole virions via intramuscular (i.m.) injections. The presence of the antibody correlated with the degree of protection. Beyond day 1 post challenge infection (p.i.), there was no virus shedding in the nasal mucus of foals immunized with whole EHV-1 virions. Virus shedding was observed in foals Immunized with L-particles but limited to days 6 to 8 p.i. only. In contrast, extended vim shedding was observed in non-immunized foals and it was well beyond day 14 p.i. Viremia was not detected for more than four days except in non-immunized foals. Immunization in mice via intranasal (i.n.) conferred good protection. However, compared to the i.n. route, a greater degree of protection was obtained in foals following immunization via i.m. route. Despite variation in the degree of protection due to different routes of immunization in the two animal species, our results have established significant evidence that immunization with L-particles confers protection in the natural host. It is suggested that non-infectious L-particles should be used as immunizing agents for vaccination of horses against EHV-1 infection.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.536-557
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• 2020

Sugarcane yellow leaf virus (SCYLV) is a distinct member of the Polerovirus genus of the Luteoviridae family. SCYLV is the major limitation to sugarcane production worldwide and presently occurring in most of the sugarcane growing countries. SCYLV having high genetic diversity within the species and presently ten genotypes are known to occur based on the complete genome sequence information. SCYLV is present in almost all the states of India where sugarcane is grown. Virion comprises of 180 coat protein units and are 24-29 nm in diameter. The genome of SCYLV is a monopartite and comprised of single-stranded (ss) positive-sense (+) linear RNA of about 6 kb in size. Virus genome consists of six open reading frames (ORFs) that are expressed by sub-genomic RNAs. The SCYLV is phloem-limited and transmitted by sugarcane aphid Melanaphis sacchari in a circulative and non-propagative manner. The other aphid species namely, Ceratovacuna lanigera, Rhopalosiphum rufiabdominalis, and R. maidis also been reported to transmit the virus. The virus is not transmitted mechanically, therefore, its transmission by M. sacchari has been studied in different countries. SCYLV has a limited natural host range and mainly infect sugarcane (Sachharum hybrid), grain sorghum (Sorghum bicolor), and Columbus grass (Sorghum almum). Recent insights in the protein-protein interactions of Polerovirus through protein interaction reporter (PIR) technology enable us to understand viral encoded proteins during virus replication, assembly, plant defence mechanism, short and long-distance travel of the virus. This review presents the recent understandings on virus biology, diagnosis, genetic diversity, virus-vector and host-virus interactions and conventional and next generation management approaches.