• 미생물학회지
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• 제38권4호
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• pp.260-266
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• 2002

Ralstonia eutropha JMP134로부터 페놀대사의 조절에 관여하는 유전자부위를 cloning하여 염기서열을 파악하였으며 그 특성을 조사하였다. 염기서열 분석 결과 두 개의 open reading frame (ORF1 & ORF2)들을 발견하였다. ORF1은 페놀분해 구조유전자중의 마지막 인자인phlX의 stop codon으로부터 454 bp 아래에서 시작하여 총 501 개의 아미노산으로 구성되었으며 ORF2는 ORF1의 stop codon으로부터 1 bP 위쪽에서 4개의 염기쌍과 중첩된 상태에서 시작하여 총 232개의 아미노산으로 구성되어 있는 것으로 나타났다. 단백질 배열을 분석해본 결과 ORF1은 transcriptional activator로 작용하는 NtrC family에 속하는 것으로 확인되었으며, ORF2는 negative regulator로 알려진 GntR family에 속하는 것으로 나타났다. ORF1과 ORF2를 encoding하는 유전자를 각각 phlR2 와 phlA로 명명하였으며 이들의 가능한 조절기작을 고찰하였다.

• International Journal of Oral Biology
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• 제40권1호
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• pp.19-25
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• 2015

Osteocytes may function as mechanotransducers by regulating local osteoclastogenesis. Reduced availability of oxygen, i.e. hypoxia, could occur during disuse, bone development, and fracture. Receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) is an osteoblast/stromal cell derived essential factor for osteoclastogenesis. The hypoxia induced osteoclastogenesis via increased RANKL expression in osteoblasts was demonstrated. Hypoxic regulation of gene expression generally involves activation of the hypoxia-inducible factor (HIF) transcription pathway. In the present study, we investigated whether hypoxia regulates RANKL expression in murine osteocytes and HIF-$1{\alpha}$ mediates hypoxia-induced RANKL expression by transactivating RANKL promoter, to elucidate the role of osteocyte in osteoclastogenesis in the context of hypoxic condition. The expression levels of RANKL mRNA and protein, as well as hypoxia inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) protein, were significantly increased in hypoxic condition in MLO-Y4s. Constitutively active HIF-$1{\alpha}$ alone significantly increased the levels of RANKL expression in MLO-Y4s under normoxic conditions, whereas dominant negative HIF-$1{\alpha}$ blocked hypoxia-induced RANKL expression. To further explore to find if HIF-$1{\alpha}$ directly regulates RANKL transcription, a luciferase reporter assay was conducted. Hypoxia significantly increased RANKL promoter activity, whereas mutations of putative HIF-$1{\alpha}$ binding elements in RANKL promoter prevented this hypoxia-induced RANKL promoter activity in MLO-Y4s. These results suggest that HIF-$1{\alpha}$ mediates hypoxia-induced up-regulation of RANKL expression, and that in osteocytes of mechanically unloaded bone, hypoxia enhances osteoclastogenesis, at least in part, via an increased RANKL expression in osteocytes.

• 융합정보논문지
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• 제7권6호
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• pp.89-95
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• 2017

암을 유발하는 PMA는 세포를 자극하여 전사인자 C-Jun/C-fos의 발현을 증가시키며 핵 내의 AP-1의 활성을 증가하게 되고 결과적으로 각종 암이 발생된다고 보고되고 있다. 본 연구에서는 천연물 지표성분의 안전성을 보기위한 세포독성과 암예방 효과를 예측할 수 있는 Activator protein(AP-1) 활성억제를 관찰하였다. 천연물 지표성분 38종을 대상으로 세포독성과 AP-1 활성억제를 관찰한 결과 섬수의 지표성분인 Bufogein 과 Cinobufagin에서는 세포독성을 보이며 AP-1 활성 억제와 비교 시 5배 정도 차이를 보임을 알 수가 있다. 반면에 Arctigenin, Manassantin A, B에서는 AP-1 활성 억제 농도는 $2{\mu}M$ 이하이면서 세포독성과의 비율은 15배 이상임을 알 수 있다. 본 실험의 결과를 통해 우방자와 삼백초의 지표성분인 Arctigenin, Manassantin A,B는 암 예방 연구의 가능성을 시사하였다.

• 대한골관절종양학회지
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• 제5권3호
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• pp.162-168
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• 1999

c-fos와 c-jun은 암 유전자의 하나이며, 이 유전자의 단백질 산물은 여러 가지의 다른 활성화 단백 (activator protein 1, AP-1)으로 골 종양에서 골세포의 증식과 분화를 조절하는 중요한 역할을 하는 인자 중 하나로 알려져 있다. 본 연구에서는 단클론 항체를 이용하여 포르말린에 고정된 파라핀 포매조직을 이용하여 35례의 사람 골육종에서 c-fos 단백의 발현을 연구하였다. c-fos의 발현은 골 형성 병변에서 주로 발현되며, 저등급의 연골형성 병변에서는 발현이 관찰되지 않았다. 높은 빈도의 c-fos 단백의 발현이 골아성 골육종에서 발현되었으나 (17례 중 13례에서 1등급 내지 2등급으로 발현), 2례의 연골형성 골육종, 1례의 섬유아세포성 골육종, 2례의 방골성 골육종에서는 음성으로 나타났다. 2례의 혈관확장성 골육종에서는 양성으로 c-fos 단백의 발현되었다. 비록 조직학적으로 고등급의 골육종에서 면역조직화학적 염색상 고 빈도의 c-fos 단백의 발현이 관찰되나, 조직학적 등급과, 면역염색상 발현사이에 통계적인 유의성은 관찰되지 않았다. 이상의 결과로 c-fos 단백이 골육종의 발생에 관여할 것으로 추론되며, 저등급의 연골형성 육종에 이 단백의 역할에는 추후 연구가 필요할 것으로 사료된다.

• 대한통합의학회지
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• 제7권4호
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• pp.61-69
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• 2019

Purpose : Human gingival fibroblast cell is one of the the main cell types in periodontal tissue, which they can show anti-inflammatory activity through the production of numerous lines of inflammatory mediators such as inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 and interleukins. Porphyromonas gingivalis, one of the oral pathogens, has reported to play a critical role in the development of periodontal diseases. This study aimed to investigate anti-inflammatory and antioxidative activities of Gracilaria textorii ethanol extract (GTEE) in P. gingivalis derived lipopolysaccharide (LPS-PG) stimulated human gingival fibroblast (HGF)-1 cell line. Methods : In order to analyze anti-inflammatory and antioxidative activities of GTEE in HGF-1 cell line, NOS enzyme activity, expression levels of iNOS, COX-2, NAD(P)H quinone dehydrogenase (NQO)1 and their transcription factors were estimated by Griess reaction and western hybridization. Results : LPS-PG induced overexpression of iNOS and COX-2, which was significantly attenuated by GTEE treatment in a dose-dependent manner without any cytotoxicity. In addition, intracellular NOS activity was in accordance with the result of iNOS expression. Due to important role in the regulation of inflammatory responses, phosphorylated status of p65 and c-jun, each subunit of nuclear factor (NF)-κB and activator protein (AP)-1, was also dose-dependently ameliorated by GTEE treatment. One of phase II enzymes, NQO1, and its transcription factor, nuclear factor erythroid 2-related factor 2 (Nrf2), were analyzed since elevated phase II enzyme expression inhibited inflammatory response, which was significantly elevated by GTEE treatment in HGF-1 cell line. Conclusion : In conclusion, GTEE mitigated LPS-PG-stimulated inflammatory responses by attenuating NF-κB and AP-1 activation as well as accelerating NQO1 and Nrf2 expression in HGF-1 cell line. These results indicate that GTEE might be utilized a promising strategy for potential anti-inflammatory agent in periodontal diseases.

• BMB Reports
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• 제42권11호
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• pp.758-763
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• 2009

Cancer-associated antigen (CAGE) induces the expression of matrix metalloproteinase-2 (MMP-2) by activating Akt, which in turn interacts with inhibitory kappa kinase $\beta$ ($I{\kappa}K{\beta}$) to activate nuclear factor ${\kappa}B$ (NF-${\kappa}B$). Akt and p38 mitogen activated protein kinase (p38 MAPK) are necessary for CAGE-mediated induction of the AP-1 subunit JunB, whereas extracellular regulated kinase (ERK) is necessary for the induction of fos-related antigen-1 (Fra-1). Induction of MMP-2 by CAGE requires activator of protein-1 (AP-1) to be bound. Specific binding of JunB to MMP-2 promoter sequences was shown by chromatin immunoprecipitation (ChIP) analysis.

• 한국축산식품학회지
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• 제37권6호
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• pp.917-925
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• 2017

Whey protein, a by-product of milk curdling, exhibits diverse biological activities and is used as a dietary supplement. However, its effects on stress-induced vascular aging have not yet been elucidated. In this study, we found that whey protein significantly inhibited the Ang II-primed premature senescence of vascular smooth muscle cells (VSMCs). In addition, we observed a marked dose- and time-dependent increase in SIRT1 promoter activity and mRNA in VSMCs exposed to whey protein, accompanied by elevated SIRT1 protein expression. Ang II-mediated repression of SIRT1 level was dose-dependently reversed in VSMCs treated with whey protein, suggesting that SIRT1 is involved in preventing senescence in response to this treatment. Furthermore, resveratrol, a well-defined activator of SIRT1, potentiated the effects of whey protein on Ang II-primed premature senescence, whereas sirtinol, an inhibitor of SIRT1, exerted the opposite. Taken together, these results indicated that whey protein-mediated upregulation of SIRT1 exerts an anti-senescence effect, and can thus ameliorate Ang II-induced vascular aging as a dietary supplement.

• The Korean Journal of Physiology and Pharmacology
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• 제12권5호
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• pp.259-265
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• 2008

$[Ca^{2+}]_i$ transients by reverse mode of cardiac $Na^+/Ca^{2+}$ exchanger (NCX1) were recorded in fura-2 loaded BHK cells with stable expression of NCX1. Repeated stimulation of reverse NCX1 produced a long-lasting decrease of $Ca^{2+}$ transients ('rundown'). Rundown of NCX1 was independent of membrane $PIP_2$ depletion. Although the activation of protein kinase C (PKC) was observed during the $Ca^{2+}$ transients, neither a selective PKC inhibitor (calphostin C) nor a PKC activator (PMA) changed the degrees of rundown. By comparison, a non-specific PKC inhibitor, staurosporine (STS), reversed rundown in a dose-dependent and reversible manner. The action of STS was unaffected by pretreatment of the cells with calphostin C, PMA, or forskolin. Taken together, the results suggest that the stimulation of reverse NCX1 by STS is independent of PKC and/or PKA inhibition.

• Journal of Microbiology and Biotechnology
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• 제28권2호
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• pp.190-198
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• 2018

Periodontitis is an inflammatory disease caused by microbial lipopolysaccharide (LPS), destroying gingival tissues and alveolar bone in the periodontium. In the present study, we evaluated the anti-inflammatory and anti-osteoclastic effects of panduratin A, a chalcone compound isolated from Boesenbergia pandurata, in human gingival fibroblast-1 (HGF-1) and RAW 264.7 cells. Treatment of panduratin A to LPS-stimulated HGF-1 significantly reduced the expression of interleukin-$1{\beta}$ and nuclear factor-kappa B (NF-${\kappa}B$), subsequently leading to the inhibition of matrix metalloproteinase-2 (MMP-2) and MMP-8 compared with that in the LPS control ($^{**}p$ < 0.01). These anti-inflammatory responses were mediated by suppressing the mitogen-activated protein kinase (MAPK) signaling and activator protein-1 complex formation pathways. Moreover, receptor activator of NF-${\kappa}B$ ligand (RANKL)-stimulated RAW 264.7 cells treated with panduratin A showed significant inhibition of osteoclastic transcription factors such as nuclear factor of activated T-cells c1 and c-Fos as well as osteoclastic enzymes such as tartrate-resistant acid phosphatase and cathepsin K compared with those in the RANKL control ($^{**}p$ < 0.01). Similar to HGF-1, panduratin A suppressed osteoclastogenesis by controlling MAPK signaling pathways. Taken together, these results suggest that panduratin A could be a potential candidate for development as a natural anti-periodontitis agent.

• Journal of Plant Biotechnology
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• 제38권1호
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• pp.94-104
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• 2011

Salt stress is a major environmental factor influencing plant growth and development. To identify salt tolerance determinants, we systematically screened salt sensitive rice mutants by use of the Activator/Dissociation (Ac/Ds) transposon tagging system. In this study, we focused on the salt sensitive mutant line, designated SSM-1. A gene encoding a NAC transcription factor homologue was disrupted by the insertion of a Ds transposon into SSM-1 line. The OsNAC075 gene (EU541472) has 7 exons and encodes a protein (486-aa) containing the NAC domain in its N-terminal region. Sequence comparison showed that the OsNAC075 protein had a strikingly conserved region at the N-terminus, which is considered as the characteristic of the NAC protein family. OsNAC075 protein was orthologous to Arabidopsis thaliana ANAC075. Phylogenetic analysis confirmed OsNAC075 belonged to the OsNAC3 subfamily, which plays an important role in response to stress stimuli. RT-PCR analysis showed that the expression of OsNAC075 gene was rapidly and strongly induced by stresses such as NaCl, ABA and low temperature ($4^{\circ}C$). Our data suggest that OsNAC075 holds promising utility in improving salt tolerance in rice.