• Molecules and Cells
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• v.23 no.3
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• pp.304-315
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• 2007

Fusarium graminearum causes a serious scab disease of small grains in Korea. The nucleotide sequence of the genomic RNA of a double-stranded RNA (dsRNA) virus, Fusarium graminearum virus-DK21 (FgV-DK21), from F. graminearum strain DK21, which is associated with hypovirulence in F. graminearum, was determined and compared to the genome sequences of other mycoviruses, including Cryponectria hypoviruses. The FgV-DK21 dsRNA consists of 6,624 nucleotides, excluding the 3'-terminal poly(A) tail. The viral genome has 53- and 46-nucleotide 5' and 3' untranslated regions (UTRs), respectively, and five putative open reading frames. A phylogenetic analysis of the deduced amino acid sequence of ORF1, which encodes a putative RNA-dependent RNA polymerase, and those of other mycoviruses revealed that this organism forms a distinct virus clade with other hypoviruses, and is more distantly related to other mycoviruses (3.8 to 24.0% identity). However, pairwise sequence comparisons of the nucleotide and deduced amino acid sequences of ORFs 2 through 5 revealed no close relationships to other protein sequences currently available in GenBank. Analyses of RNA accumulation by Northern blot and primer extension indicated that these putative gene products are expressed from at least two different subgenomic RNAs (sgRNAs), in contrast to the cases in other hypoviruses. This study suggests the existence of a new, as yet unassigned, genus of mycoviruses that exhibits a potex-like genome organization and sgRNA accumulation.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2626-2630
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• 2009

2'($\beta$)-Hydroxymethylated adenosine is a potent and selective inhibitor of hepatitis C virus (HCV) replication. It targets the RNA-dependent RNA polymerase of HCV, NS5B. Synthesis and antiviral evaluation of carbocyclic versions are described. The cyclopentene intermediate ($9\beta$) was successfully synthesized through sequential Johnson-Claisen orthoester rearrangement and ring-closing metathesis (RCM). Coupling of bases via a Pd(0) catalyst, selective dihydroxylation, and desilylation yielded the target nucleoside analogues. The compounds 17 and 18 were assayed for their ability to inhibit HCV RNA replication in a subgenomic replicon Huh7 cell line and showed moderate antiviral activity with toxicity up to 20.0 and 24.7 ${\mu}g/mL$, respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.2
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• pp.23-32
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• 1997

Melanin pigmentation in human skin is a major defense mechanism against ultraviolet light of the sun. Tyrosinase(EC 1.14.18.1) plays a key role in the biosynthesis of ultraviolet of melanin. This is why much researches have been focused on its regulation in controlling the epidermal melanization. We have found that the water-extract of Banha(Pinelliae ternate B.), an oriental medicinal plant, has no tyrosinase inhibitory activity, but does inhibit the melanin biolsynthesis in B16 mouse melanin cells. We also found that Banha extract lowers the tyrosinase activity in cultured cells. To elucidate the action mechanism of Banha extract we have investigated its effect on the tyrosinase mRNA level using reverse transcription-polymerase chain reaction technique. It was revealed that Banha extract reduced the tyrosinase mRNA level in dose dependent manner; when B16 mouse melanoma cells were cultured with 2mg/ml and 5mg/ml of Banha extract, there were 20% and 44% decrease in tyrosinase mRNA level, respectively. These data suggest that the Banha extract exerts its melanogenic inhibitory effect through the transcriptional regulation of tyrosinase mRNA.

• The Journal of Korean Society of Virology
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• v.29 no.4
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• pp.247-259
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• 1999

Small round structured viruses (SRSV) are the major ethological agents which can cause outbreaks of non-bacterial gastroenteritis or food poisoning both in children and adults. The classification of family Caliciviridae to which SRSV belong, is based on the genome encoding three open reading frames. The rotavirus is another major pathogen which causes diarrhea in young children. We examined stool specimens obtained from diarrheal patients in Wonju from which bacterial pathogens were not found. To detect causative viruses from stool specimens of patients, reverse transcription (RT)-polymerase chain reaction (PCR) or nested PCR using rotavirus or SRSV specific primers was performed. In this study, RT-nested PCR procedure which can amplify a 330 bp fragment derived from RNA dependent RNA polymerase (RDRP) region within ORF1 was applied for the detection of SRSV. For the detection of rotaviruses, a 877 bp fragment from the VP4 region of rotavirus genome was amplified. As a result, rotavirus was not detected while SRSV sequences were detected from one out of five specimens. The nucleotide and amino acid sequences of the Wonju isolate were compared with other 6 Korean isolates which have been isolated and sequenced in our laboratory. Sequence analysis revealed that the Wonju isolate was rather distinct from other Korean isolates: the Wonju isolate was closer to genogroup I of SRSV while other 6 Korean isolates belonged to genogroup II.

• The Plant Pathology Journal
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• v.20 no.3
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• pp.200-205
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• 2004

The partial nucleotide sequences of the genomic dsRNA mycovirus infecting Pleurotus ostreatus isolates ASI2223 and Suhan were determined and compared with those of mycoviruses belonging to partitiviruses and totiviruses. Partial nucleotide sequences of the purified dsRNA from ASI2223 and Suhan showed RNA-dependent RNA polymerase sequences that are closely related to those of partitiviruses, including Fusarium poae virus 1, Fusarium solani virus, Rhizoctoniasolani virus, Discula destructiva virus 2, and Oyster mushroom isometric virus 2. Specific primers were designed for RT-PCR detection of dsRNA viruses from the P. ostreatus isolate ASI2223 and Suhan. Two virus specific primer sets were found to specifically detect each virus among six sets of designed oligonucleotide primers. Collectively, these results suggest that dsRNA mycoviruses from P. ostreatus isolates ASI2223 and Suhan belong to the family Partitiviridae, although, they are not the same virus species. Our results also suggest that these virus-specific primer sets can be employed for the specific detection of each viral sequence in infected tissues.

• Journal of fish pathology
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• v.37 no.1
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• pp.1-8
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• 2024

The advantages of replicon vectors of RNA viruses include a high ability to stimulate innate immunity and exponential amplification of target mRNA leading to high expression of foreign antigens. The present study aimed to construct a DNA-layered nervous necrosis virus (NNV) replicon vector system in which the capsid protein gene was replaced with a foreign antigen gene and to compare the efficiency of foreign antigen expression between the conventional DNA vaccine vector and the present replicon vector. We presented the first report of a nodavirus DNA replicon-based foreign antigen expression system. Instead of a two-vector system, we devised a one-vector system containing both an NNV RNA-dependent RNA polymerase cassette and a foreign antigen-expressing cassette. This single-vector approach circumvents the issue of low foreign protein expression associated with the low co-transfection efficiency of a two-vector system. Cells transfected with a vector harboring hammerhead ribozyme-fused RNA1 and RNA2 (with the capsid gene ORF replaced with VHSV glycoprotein ORF) exhibited significantly higher transcription of the VHSV glycoprotein gene compared to cells transfected with either a vector without hammerhead ribozyme or a conventional DNA vaccine vector expressing the VHSV glycoprotein. Furthermore, the transcription level of the VHSV glycoprotein in cells transfected with a vector harboring hammerhead ribozyme-fused RNA1 and RNA2 showed a significant increase over time. These results suggest that NNV genome-based DNA replicon vectors have the potential to induce stronger and longer expression of target antigens compared to conventional DNA vaccine vectors.

• Restorative Dentistry and Endodontics
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• v.30 no.5
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• pp.372-384
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• 2005

The purpose of this study was to monitor the secretion of matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) by human periodontal ligament (PDL) fibroblasts stimulated with Prevotella nigrescens lipopolysaccharide (LPS), and to examine the effect of calcium hydroxide treatment on P. nigrescens LPS. LPS was extracted and purified from anaerobically cultured P. nigrescens. PDL fibroblasts were stimulated by the LPS (0, 0.1, 1, 10 ${\mu}g/ml$) or LPS (10 ${\mu}g/ml$) pretreated with 12.5 mg/ml of $Ca(OH)_2$ for 3 days, for various periods of time (12, 24, 48 h). Immunoprecipitation were performed for protein level analysis of MMP-1 MMP-2 and TIMP-1. Total RNA was isolated and real-time quantitative polymerase chain reaction (PCR) was performed for quantification of MMP-1 mRNA. According to this study, the results were as follows: 1. The p개duction of MMP-1 by stimulation with P. nigrescens LPS increased in time-dependent manner, and showed maximum value at 48 h in both protein and mRNA level. But there was no dose-dependent increas. 2. MMP-2 production time-dependently increased when stimulated with 1 and 10 ${\mu}g/ml$LPS, but there was no dose-dependent increase. 3. TIMP-1 p개duction increased to 24 h, but decreased at 48 h. It increased when stimulated with 0.1 and 1${\mu}g/ml$, but suppressed at 10 ${\mu}g/ml$ .4. P. nigrescens LPS pretreated with $Ca(OH)_2$ markedly downregulated MMP-1 gene expression.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1112-1121
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• 2018

Jeotgal is a Korean traditional fermented seafood with a high concentration of salt. In this study, we isolated lactic acid bacteria (LAB) from galchi (Trichiurus lepturus, hairtail) and myeolchi (Engraulis japonicas, anchovy) jeotgal on MRS agar and MRS agar containing 5% NaCl (MRS agar+5% NaCl), and identified them by using 16S rRNA gene sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as culture-dependent methods. We also performed polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) as a culture-independent method to identify bacterial communities. Five samples of galchi-jeotgal and seven samples of myeolchi-jeotgal were collected from different regions in Korea. A total of 327 and 395 colonies were isolated from the galchi- and myeolchi-jeotgal samples, respectively. 16S rRNA gene sequencing and MALDI-TOF MS revealed that the genus Pediococcus was predominant on MRS agar, and Tetragenococcus halophilus on MRS agar+5% NaCl. PCR-DGGE revealed that T. halophilus, Tetragenococcus muriaticus, and Lactobacillus sakei were predominant in both types of jeotgal. T. halophilus was detected in all samples. Even though the same species were identified by both culture-dependent and -independent methods, many species identified by the culture-dependent methods were not in the bacterial list identified by the culture-independent methods. The distribution of bacteria in galchi-jeotgal was more diverse than in myeolchi-jeotgal. The diverse LAB in galchi- and myeolchi-jeotgals can be further studied as candidates for starter cultures to produce fermented foods.

• Journal of fish pathology
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• v.22 no.2
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• pp.147-153
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• 2009

To study the biological activity of interleukin-$1\beta$(IL-$1\beta$), a proinflammatory cytokine, in nile tilapia, Oreochromis niliticus, the recombinant tilapia IL-$1\beta$ was produced in E. coli cells based on pQE vector. Ni-NTA (nitriloacetic acid) metal affinity chromatography was used to purify recombinant protein. The eluted fractions exhibited a single band of protein with a molecular weight of about 25kDa, which is in close agreement with 25.4 kDa predicted by the cDNA sequence. The biological activity of the purified recombinant tilapia IL-$1\beta$ was tested through its effects on IL-$1\beta$ gene expression, which are known as IL-$1\beta$ inducible genes in mammals and fishes. IL-$1\beta$ gene expression induced by poly I:C, a synthetic double stranded RNA, was also assessed in tilapia head kidney cells. IL-$1\beta$ gene expression was analysed using QPCR (quantitative polymerase chain reaction). The ratio of the indicated gene expression was expressed as the relative mRNA level to $\beta$-actin mRNA level, which is constitutively expressed in macrophages. Consequently, head kidney cells incubated for three hours with rIL-$1\beta$(10, 2, 1 $\mu{g}$/ml) showed a dose dependent increase in IL-$1\beta$ mRNA levels and 1 $\mu{g}$/ml of poly I:C was also able to induce IL-$1\beta$ gene expression in head kidney in tilapia.

• The korean journal of orthodontics
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• v.39 no.4
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• pp.248-256
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• 2009

Objective: The aim of this study was to determine if human PDL cells can produce osteoclastogenic mRNA and examine how compressive stress affects the expression of osteoclastogenic mRNA in human PDL cells. Methods: Human PDL cells were obtained from biscupids extracted for orthodontic treatment. The compressive force was adjusted by increasing the number of cover glasses. PDL cells were subjected to a compressive force of 0.5, 1.0, 2.0, 3.0 or $4.0\;g/cm^2$ for 0.5, 1.5, 6, 24 or 48 hours. Reverse transcription polymerase chain reaction (RT-PCR) analysis was performed to examine levels of M-CSF, IL-$1{\beta}$, RANKL, OPG mRNA expression. Results: Human PDL cells could produce M-CSF mRNA. Human PDL cells under compressive stress showed increased M-CSF, IL-$1{\beta}$ and RANKL mRNAs expression in a force (up to $2\;g/cm^2$) and time-dependent manner. However, OPG mRNA expression was constant regardless of the level and duration of stress. Conclusions: Continuous compressive stress induced the mRNA expression of osteoclastogenic cytokines including M-CSF, RANKL, IL-$1{\beta}$ in PDL cells. Together with an unchanged OPG mRNA level, these results suggest that compressive stress-induced osteoclastogenesis in vivo is partly controlled by M-CSF, RANKL and IL-$1{\beta}$ expression in PDL cells.