• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.646-650
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• 1985

RNA degradation by riboinuclease A (EC 3.1.27.5) was inhibited by spermine. As the concentration of spermine was increased, the ribonuclease activity was decreased gradually until it reached a plateau. Under the same conditions, the viscosity of the RNA increased, as the spermine concentration was increased until it reached a plateau in the same manner as the profile of the spermine-dependent ribonuclease activity. The inhibitory effect of spermine on the susceptibility of RNA to the ribonuclease could be relieved by denatured calf thymus DNA, but not by the native DNA. The data here indicate the possibility that the suppress of the RNA susceptibility for the ribonuclease by spermine is brought about by the spermine-induced intermolecular aggregation of the RNA molecules.

• Biomedical Science Letters
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• v.29 no.4
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• pp.231-241
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• 2023

Messenger RNA (mRNA)-based vaccines and treatments have recently emerged as a promising strategy. Naked mRNA presents various limitations for direct delivery. Therefore, in this paper, Lipid Nanoparticles (LNPs) were utilized for the delivery of mRNA. Lipid nanoparticle (LNP) mRNA systems are highly effective as vaccines, but their efficacy for pulmonary delivery has not yet been fully established. Additionally, research on effective delivery systems and administration methods for vaccines is required to resolve the stability and degradation issues associated with naked mRNA delivery. This study aimed to determine mRNA delivery efficiency via the inhalation of a lipid nanoparticle (LNP) formulation designed specifically for pulmonary delivery. To this purpose, we built a library of seven LNP configurations with different lipid molar and N/P ratios and evaluated their encapsulation efficiency using gel retardation assay. Among the tested LNPs, LNP1, LNP2-2, and LNP3-2 demonstrated high transfection efficiency in vitro based on FACS analyses luciferase assays, and intracellular accumulation tests. The mRNA delivery efficiencies of the selected LNPs after inhalation and intravenous injection were compared and evaluated. LNP2-2 showed the highest mRNA expression in healthy mouse lungs when aerosolized and was found to be non-toxic. These results indicate that LNP2-2 is a promising carrier for lung mRNA delivery via inhalation.

• BMB Reports
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• v.30 no.4
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• pp.258-261
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• 1997

A simple quantitative assay method for ribonuclease activity has been developed. This method is based on the decrease of fluorescence intensity emitted by the ethidium bromide bound to RNA due to the degradation of RNA by ribonuclease. The substrate RNA was reacted with ribonuclease A and the fluorescence intensity was measured after the addition of ethidium bromide. The intensity difference was calculated using a blank reaction mixture containing no RNase. Whole cellular RNA substrate produced a significant error and was not suitable for this assay method possibly because of local microheterogeniety caused by high molecular weight rRNA. but satisfying results were obtained with tRNA substrate. The intensity difference increased linearly by raising enzyme concentration up to $2{\times}10^{-4}$ Kunitz Units of ribonuclease A. More refined and reliable results were obtained by use of initial reaction velocities which were calculated from the plots of intensity difference vs time. A linear relationship between initial velocities and enzyme concentrations was observed up to 0.01 Kunitz Units of enzyme.

• Mass Spectrometry Letters
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• v.13 no.4
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• pp.115-124
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• 2022

Emerging evidence has shown that RNA-binding proteins (RBPs) dynamically regulate all aspects of RNA in cells and involve in major biological processes of RNA, including splicing, modification, transport, transcription and degradation. RBPs, as powerful and versatile regulatory molecule, are essential to maintain cellular homeostasis. Perturbation of RNA-protein interactions and aberration of RBPs function is associated with diverse diseases, such as cancer, autoimmune disease, and neurological disorders. Therefore, it is crucial to systematically investigate the RNA-binding proteome for understanding interactions of RNA with proteins. Thanks to the development of the mass spectrometry, a variety of proteome-wide methods have been explored to define comprehensively RNA-protein interactions in recent years and thereby contributed to speeding up the study of RNA biology. In this review, we systematically described these methods and summarized the advantages and disadvantages of each method.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.223-227
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• 2010

RNase E plays a major role in the degradation and processing of a large number of RNA transcripts in Escherichia coli and forms the core component of the degradosome, a large protein complex involved in RNA metabolism. RraA and RraB are recently discovered protein inhibitors of RNase E and are evolutionarily conserved. In this study, we observed that, unlike RraA, overexpression of RraB did not rescue growth arrest of E. coli cells overexpressing RNase E. To examine whether this phenomenon stems from differential inhibitory effects of RraA and RraB on RNase E substrates, we analyzed three in vivo RNase E substrates. The results showed that RraA inhibited RNase E activity more efficiently than RraB on the degradation of RNA I, which controls the copy number of ColE1-type plasmid, and rpsO mRNA encoding ribosomal protein S15, while RraB was unable to inhibit the processing of pM1 RNA, a precursor of the RNA component of RNase P, by RNase E. Our results imply that RraB inhibits RNase E activity in a more substrate-dependent manner than RraA and this property of RraB may explain why overexpression of RraB could not rescue cells overexpressing RNase E from growth arrest.

• Molecules and Cells
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• v.46 no.1
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• pp.10-20
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• 2023

Antisense oligonucleotide (ASO) technology has become an attractive therapeutic modality for various diseases, including Mendelian disorders. ASOs can modulate the expression of a target gene by promoting mRNA degradation or changing pre-mRNA splicing, nonsense-mediated mRNA decay, or translation. Advances in medicinal chemistry and a deeper understanding of post-transcriptional mechanisms have led to the approval of several ASO drugs for diseases that had long lacked therapeutic options. For instance, an ASO drug called nusinersen became the first approved drug for spinal muscular atrophy, improving survival and the overall disease course. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause cystic fibrosis (CF). Although Trikafta and other CFTR-modulation therapies benefit most CF patients, there is a significant unmet therapeutic need for a subset of CF patients. In this review, we introduce ASO therapies and their mechanisms of action, describe the opportunities and challenges for ASO therapeutics for CF, and discuss the current state and prospects of ASO therapies for CF.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.278-284
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• 2011

The CCR4-CAF1-NOT complex-mediated degradation of mRNA is a fundamental aspect of gene regulation in eukaryotes. We herein examined the role of AtCAF1 in the innate immune and wound responses of plants. Our results showed that overexpression of AtCAF1 significantly downregulated the transcript level of EFR but not FLS2 and BRI1, as well as abolished up-regulated expression pattern of EFR in response to wounding. Consistently, Agrobacteriummediated transient expression of GUS was highly enhanced in the transgenic plants overexpressing AtCAF. Furthermore, JA responsive genes were down-regulated by overexpression of AtCAF, causing the transgenic plants overexpressing AtCAF more susceptible to necrotrophic fungal pathogen, Botrytis cinerea. These results suggest that The CCR4-CAF1-NOT complex-mediated degradation of mRNA negatively regulates wounding-mediated disease resistance in Arabidopsis thaliana.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.651-657
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• 2009

Shifts in the activity and diversity of microbes involved in aliphatic and aromatic hydrocarbon degradation in contaminated soil were investigated. Subsurface soil was collected from a gas station that had been abandoned since 1995 owing to ground subsidence. The total petroleum hydrocarbon content of the sample was approximately 2,100 mg/kg, and that of the soil below a gas pump was over 23,000 mg/kg. Enrichment cultures were grown in mineral medium that contained hexadecane (H) or naphthalene (N) at a concentration of 200 mg/l. In the Henrichment culture, a real-time PCR assay revealed that the 16S rRNA gene copy number increased from $1.2{\times}10^5$to $8.6{\times}10^6$with no lag phase, representing an approximately 70-fold increase. In the N-enrichment culture, the 16S rRNA copy number increased about 13-fold after 48 h, from $6.3{\times}10^4$to $8.3{\times}10^5$. Microbial communities in the enrichment cultures were studied by denaturing gradient gel electrophoresis and by analysis of 16S rRNA gene libraries. Before the addition of hydrocarbons, the gas station soil contained primarily Alpha- and Gammaproteobacteria. During growth in the H-enrichment culture, the contribution of Bacteriodetes to the microbial community increased significantly. On the other hand, during N-enrichment, the Betaproteobacteria population increased conspicuously. These results suggest that specific phylotypes of bacteria were associated with the degradation of each hydrocarbon.

• Korean Journal of Oriental Medicine
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• v.16 no.3
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• pp.155-166
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• 2010

Objetives : The purpose of this study was to examine the pathway of anti-allergic effects of Aconiti Ciliare Tuber (ACT). Methods : We examined cell viability, ${\beta}$-hexosaminidase release, pro-inflammatory cytokines secretion and mRNA expressions, nuclear factor-kappa B (NF-${\kappa}B$) (p65) activation, inhibitor kappa B-alpha ($I{\kappa}B-{\alpha}$) degradation, and MAPKs activation from RBL-2H3 cells pre-treatment by ACT of 1.0 mg/ml, 2.0 mg/ml separately. Results : We observed that ACT reduced the secretion of ${\beta}$-hexosaminidase, TNF-${\alpha}$, IL-4 and the expression of COX-2 mRNA in RBL-2H3 cells. Futhermore, ACT inhibited the levels of activation of NF-${\kappa}B$ (p65) protein, ERK MAPK, and degradation of $I{\kappa}B-{\alpha}$ in RBL-2H3 cells. Conclusions : These results show that ACT has an anti-histamine effect and inhibitory effect of NF-${\kappa}B$ (p65) through regulation of $I{\kappa}B-{\alpha}$ degradation. This improves that ACT could be used as an anti-allergic medicine.

• The Journal of Pediatrics of Korean Medicine
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• v.24 no.1
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• pp.93-103
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• 2010

Objectives The purpose of this study was to examine the pathway of anti-allergic effects of Cheonmaec-tang (CMT). Methods We examined the cell viability, $\beta$-hexosaminidase release, pro-inflammatory cytokines secretion and mRNA expressions, nuclear factor-kappa B (NF-${\kappa}B$) (p65) activation, inbibitor kappa B-alpha ($I{\kappa}B-{\alpha}$) degradation, and MAPKs activation in RBL-2H3 cells pre-treated by CMT of 2.0 mg/ml, 4.0 mg/ml separately. Results We observed that CMT reduced the secretion of $\beta$-hexosaminidase, TNF-$\alpha$, IL-4 and the expression of COX-2 mRNA in RBL-2H3 cells. Furthermore, CMT inhibited the levels of activation of NF-${\kappa}B$ (p65) protein, ERK MAPK, and degradation of $I{\kappa}B-{\alpha}$ in RBL-2H3 cells. Conclusions These results show that CMT has an anti-histamine effect and inhibitory effect of NF-${\kappa}B$ (p65) through regulation of $I{\kappa}B-{\alpha}$ degradation. These suggest that CMT could be used as an anti-allergic medicine.