• The Plant Pathology Journal
• /
• v.27 no.4
• /
• pp.310-314
• /
• 2011

Nonstructural protein 3 (NS3) encoded by RNA3 of Rice stripe virus (RSV), known to be a suppressor of gene silencing, was cloned and sequenced. The cloned NS3 gene is composed of 636 nucleotides encoding 211 deduced amino acids, and showed a high degree of similarity with the equivalent genes isolated from Korea, Japan and China. The NS3 gene promoted the enhancement of transient gene expression and suppressed transgene co-silencing. In the transient GFP expression via agroinfiltration, GFP expression was dramatically enhanced in terms of both protein yield and expression period in the presence of NS3. The highest accumulation of GFP protein reached to 6.8% of total soluble proteins, which corresponded to a two-fold increase compared to that obtained in the absence of NS3. In addition, NS3 significantly suppressed the initiation of GFP co-silencing induced by the additive GFP infiltration in GFP-transgenic Nicotiana benthamiana. The NS3 gene was also found to be a stronger suppressor than Cucumber mosaic virus 2b. These observations are believed to be derived from the strong suppressive effect of NS3 on gene silencing, and indicate that NS3 could be used as an effective enhancer for the rapid production of foreign proteins in plants.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.6
• /
• pp.830-838
• /
• 2020

The histone-like nucleoid structuring protein (H-NS) is an abundant global regulator of environmentally controlled gene expression. Herein, we demonstrate that H-NS represses the expression of LeuO, the master regulator of the cyclic(Phe-Pro)-dependent signaling pathway, by directly binding to the upstream region of the gene. H-NS binds to a long stretched region (more than 160-bp long), which overlaps with binding sites for ToxR and LeuO. A high quantity of H-NS outcompetes ToxR for binding to the cis-acting element of leuO. However, our footprinting analyses suggests that the binding of H-NS is relatively weaker than LeuO or ToxR at the same molarity. Considering that the DNA nucleotide sequences of the upstream regions of leuO genes are highly conserved among various Vibrio, such patterns as those found in V. vulnificus would be a common feature in the regulation of leuO gene expression in Vibrionaceae. Taken together, these results suggest that, in species belonging to Vibrionaceae, H-NS regulates the expression of leuO as a basal stopper when cFP-ToxR mediated signaling is absent.

• Korean Journal of Microbiology
• /
• v.54 no.1
• /
• pp.1-8
• /
• 2018

A prokaryotic cell has various histone-like proteins also known as nucleoid-associated proteins (NAPs). These proteins bind AT-rich sequence at DNA, which induce DNA wrapping, bending, and bridging, and subsequently regulate the gene expression in bacteria. Because NAPs function in transcriptional silencing of virulence genes, it is important to study their roles in gene silencing and specific mechanisms of these proteins. In this review, we discussed two well-known NAPs, H-NS, and HU, and summarized their roles for gene expression in Escherichia coli and Salmonella Typhimurium. Through the oligomerization and filamentation of H-NS, it represses the expression of virulence genes in human pathogenic bacteria, such as Salmonella Typhimurium, and it works with other NAPs positively or negatively. Recently, H-NS also regulates typhoid toxin expression, which causes typhoid fever and systemic disease in human. Additionally, HU regulates the expression of genes related to both virulence and physiology of Salmonella. Therefore, we suggest that NAPs like H-NS and HU are crucial factors to reveal the molecular mechanisms of virulence gene expression in bacteria.

• Molecules and Cells
• /
• v.24 no.2
• /
• pp.215-223
• /
• 2007

The genes encoding non-specific lipid transfer proteins (nsLTPs), members of a small multigene family, show a complex pattern of expressional regulation, suggesting that some diversification may have resulted from changes in their expression after duplication. In this study, the evolution of nsLTP genes within the Poaceae family was characterized via a survey of the pseudogenes and unigenes encoding the nsLTP in rice pseudomolecules and the NCBI unigene database. nsLTP-rich regions were detected in the distal portions of rice chromosomes 11 and 12; these may have resulted from the most recent large segmental duplication in the rice genome. Two independent tandem duplications were shown to occur within the nsLTP-rich regions of rice. The genomic distribution of the nsLTP genes in the rice genome differs from that in wheat. This may be attributed to gene migration, chromosomal rearrangement, and/or differential gene loss. The genomic distribution pattern of nsLTP genes in the Poaceae family points to the existence of some differences among cereal nsLTP genes, all of which diverged from an ancient gene. The unigenes encoding nsLTPs in each cereal species are clustered into five groups. The somewhat different distribution of nsLTP-encoding EST clones between the groups across cereal species imply that independent duplication(s) followed by subfunctionalization (and/or neofunctionalization) of the nsLTP gene family in each species occurred during speciation.

• Journal of Life Science
• /
• v.25 no.11
• /
• pp.1304-1310
• /
• 2015

The period circadian clock gene 3 (PER3) plays a role in the mammalian circadian clocksystem. A regular exercise regime may affect the PER3 transcription in skeletal muscle. Although the effects of day length on circadian and circannual processes are well established in humans and mice, the influence of exercise on these processes in the horse has not been investigated. The present study investigated the expression of the PER3 gene following exercise in a thoroughbred breed of Korean horse. In addition, a comprehensive in silico nonsynonymous single nucleotide polymorphism (nsSNP) analysis of the horse PER3 gene and predicted effects of nsSNPs on proteins were examined. The expression of PER3 in skeletal muscle was significantly upregulated after exercise. Four nsSNPs were functionally annotated and analyzed by computational prediction. The total free energy and RMSD values of PER3 gene showed causative mutations. The results showed that nsSNP s395916798 (G72R) was associated with residues that have stabilizing effects on structure and function of PER3 gene. This study documented role of PER3 gene in phenotypic adaptation related to exercise in skeletal muscle. Further, the SNPs in PER3 could serve as useful biomarkers of early recovery after exercise in racehorses.

• The Korean Journal of Malacology
• /
• v.30 no.4
• /
• pp.391-397
• /
• 2014

Previously, we have reported expressed sequence tags (ESTs) analysis on the land snail, Nesiohelix samarangae (Ns). Of these ESTs, we have identified four partial fragments of N. samarangae cytochrome oxydase I (NsCO-I) gene which lead to obtain an 852 bp partial cDNA. Since NsCO-I is one of the best-known molecular phylogenetic markers, we have attempted to conduct comparative in silico analysis by using the NsCO-I gene. The combined results from BLAST analyses, multiple sequence alignment and molecular phylogenetic study of NsCO-I cDNA indicate that N. samarangae has similarity to three land snails such as Elona quimperiana, Euhadra herklotsi and Euhadra idzumonis.

• Korean Journal of Oriental Medicine
• /
• v.14 no.1
• /
• pp.145-160
• /
• 2008

Nelumbinis Semen(NS) has been used in traditional medicine to treat diseases such as depression and diarrhea. In inflammatory responses, microglia produces molecules which are known to play roles in the central nervous system. And we previously studied NS inhibited nitric oxide synthase and secretion of tumor necrosis factor alpha. To explore the global gene expression profiles in BV-2 microglial cell line treated with NS, microarray analysis was performed. The cells were treated with LPS or NS plus LPS for 30min, Ih, 3h, and 6h, respectively. Of 45,101 known genes, with cutoff value of 3-fold change in the expression, 340, 644, 280 and 219 genes were upregulated and 503, 570, 694 and 484 were downregulated in NS treated cells at each time point. The results of the present study shows that treatment of NS reversed the LPS-induced upregulation of such genes as Ecoxsackievirus and adenovirus receptor(CAR), pellino 1, and S100P binding protein. It is thought that microarrays will play an ever-growing role in the advance of our understanding of the pharmacologic actions NS.

• Molecules and Cells
• /
• v.40 no.3
• /
• pp.202-210
• /
• 2017

The nonstructural protein 5A (NS5A) encoded by the human hepatitis C virus (HCV) RNA genome is a multifunctional phosphoprotein. To analyse the influence of NS5A on apoptosis, we established an Hep-NS5A cell line (HepG2 cells that stably express NS5A) and induced apoptosis using tumour necrosis factor $(TNF)-{\alpha}$. We utilised the MTT assay to detect cell viability, real-time quantitative polymerase chain reaction and Western blot to analyse gene and protein expression, and a luciferase reporter gene experiment to investigate the targeted regulatory relationship. Chromatin immunoprecipitation was used to identify the combination of $NF-{\kappa}B$ and miR-503. We found that overexpression of NS5A inhibited $TNF-{\alpha}$-induced hepatocellular apoptosis via regulating miR-503 expression. The cell viability of the $TNF-{\alpha}$ induced Hep-mock cells was significantly less than the viability of the $TNF-{\alpha}$ induced Hep-NS5A cells, which demonstrates that NS5A inhibited $TNF-{\alpha}$-induced HepG2 cell apoptosis. Under $TNF-{\alpha}$ treatment, miR-503 expression was decreased and cell viability and B-cell lymphoma 2 (bcl-2) expression were increased in the Hep-NS5A cells. Moreover, the luciferase reporter gene experiment verified that bcl-2 was a direct target of miR-503, NS5A inhibited $TNF{\alpha}$-induced $NF-{\kappa}B$ activation and $NF-{\kappa}B$ regulated miR-503 transcription by combining with the miR-503 promoter. After the Hep-NS5A cells were transfected with miR-503 mimics, the data indicated that the mimics could reverse $TNF-{\alpha}$-induced cell apoptosis and blc-2 expression. Collectively, our findings suggest a possible molecular mechanism that may contribute to HCV treatment in which NS5A inhibits $NF-{\kappa}B$ activation to decrease miR-503 expression and increase bcl-2 expression, which leads to a decrease in hepatocellular apoptosis.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.47 no.5
• /
• pp.556-561
• /
• 2014

We applied a combination of most probable number-polymerase chain reaction (MPN-PCR) methods using a PCR procedure targeting the H-NS (VP1133) gene to detect Vibrio parahaemolyticus presence and density in seawater as well as within short-necked clam Ruditapes philippinarum tissues collected from Gomso Bay, Korea. In 30 seawater samples, V. parahaemolyticus levels ranged from less than 1.8 to $1.1{\times}10^3MPN/100mL$, and samples from August showed higher than those from other months. Furthermore, the levels of V. parahaemolyticus in six short-necked clam samples ranged from $7.8{\times}10^2$ to $2.1{\times}10^3MPN/100g$, approximately 2.5 times higher than in seawater samples from the corresponding month. Our results provide data on V. parahaemolyticus contamination in seawater and short-necked clam tissues, and help to improve quantitative methods of assessing V. parahaemolytcius levels.

• Journal of Microbiology
• /
• v.34 no.1
• /
• pp.68-73
• /
• 1996

An nprX gene of Bacillus subtilis NS15-4 encoding a neutral protease was cloned and its molecular characteristics were analyzed. The complete nucleotide sequence indicated that there is an open reading frame (0RF) possibly encoding 521 amino acid polypeptide. The ORF used all codons expected two cysteine and a proline having a codon bias index (CBI) of 0.09 in Escherichia coli. There were homologous sequences to the consensus sequence of -35 and -10 regions of E. coli promoters and to a Shine-Dalgarno (SD) sequence located 25 bp downstream of a mojor transcription initiation site. Moreover, there were also five minor transcription initiation sites at 6. 7. 8. 14 and 15 nt downstream of the major site. Northern blot analysis revealed the presence of about 1.8 kb mRNA transcript in E. coli having the nprX gene. The nucleotide sequence was identified in GenBank to be a gene for a neutral protease of B. sutilis with six nucleotide difference in the ORF region. The flanking regions of the NprX ORF showed much more differences form those of other neutral protease genes except the nprE gene of B. subtilis, which has the most homology to the nprX gene, and of which the flanking regions were identical to those of the nprX gene.