• Molecules and Cells
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• 제23권2호
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• pp.138-144
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• 2007

Previously we showed that the human GM3 synthase gene was expressed during the induction of megakaryocytic differentiation in human leukemia K562 cells by phorbol 12-myristate 13-acetate (PMA). In this study we found that treatment of PMA-induced K562 cells with $G{\ddot{o}}6976$, a specific inhibitor of PKC, and U0126, an inhibitor of the extracellular signal-regulated kinase (ERK) reduced expression of GM3 synthase, whereas wortmannin, an inhibitor of phosphoinositide 3-kinase (PI3K) did not. Moreover, activation of ERK and cAMP response element binding protein (CREB) was prevented by pretreatment with $G{\ddot{o}}6976$ and U0126. PMA stimulated the promoter activity of the 5'-flanking region from -177 to -83 region of the GM3 synthase gene, and mutation or deletion of a CREB site located around -143 of the promoter reduced PMA-stimulated promoter activity, as did the inhibitors $G{\ddot{o}}6976$ and U0126. Our results demonstrate that induction of GM3 synthase during megakaryocytic differentiation in PMA-stimulated human leukemia K562 cells depends upon the PKC/ERK/CREB pathway.

• Molecules and Cells
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• 제37권2호
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• pp.161-171
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• 2014

In several lysosomal storage disorders, including Niemann-Pick disease Type C (NP-C), sphingolipids, including glycosphingolipids, particularly gangliosides, are the predominant storage materials in the brain, raising the possibility that accumulation of these lipids may be involved in the NP-C neurodegenerative process. However, correlation of these accumulations and NP-C neuropathology has not been fully characterized. Here we derived NP-C mice with complete and partial deletion of the Siat9 (encoding GM3 synthase) gene in order to investigate the role of ganglioside in NP-C pathogenesis. According to our results, NP-C mice with homozygotic deletion of GM3 synthase exhibited an enhanced neuropathological phenotype and died significantly earlier than NP-C mice. Notably, in contrast to complete depletion, NP-C mice with partial deletion of the GM3 synthase gene showed ameliorated NP-C neuropathology, including motor disability, demyelination, and abnormal accumulation of cholesterol and sphingolipids. These findings indicate the crucial role of GM3 synthesis in the NP-C phenotype and progression of CNS pathologic abnormality, suggesting that well-controlled inhibition of GM3 synthesis could be used as a therapeutic strategy.

• Molecules and Cells
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• 제25권2호
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• pp.247-252
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• 2008

There are several branch points in the flavonoid synthesis pathway starting from chalcone. Among them, the hydroxylation of flavanone is a key step leading to flavonol and anthocyanin. The flavanone 3-${\beta}$-hydroxylase (GmF3H) gene was cloned from soybean (Glycine max cultivar Sinpaldal) and shown to convert eriodictyol and naringenin into taxifolin and dihydrokaempferol, respectively. The major flavonoids in this soybean cultivar were found by LC-MS/MS to be kamepferol O-triglycosides and O-diglycosides. Expression of GmF3H and flavonol synthase (GmFLS) was induced by ultraviolet-B (UV-B) irradiation and their expression stimulated accumulation of kaempferol glycones. Thus, GmF3H and GmFLS appear to be key enzymes in the biosynthesis of the UV-protectant, kaempferol.

• Applied Biological Chemistry
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• 제49권3호
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• pp.192-195
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• 2006

국내에서 개발된 비타민 E 강화 유전자변형 들깨의 정성 PCR 분석법의 개발을 위해 들깨의 내재 유전자로써 KAS-I (Beta-ketoacyl-ACP synthase I)를 선별하였고, 이러한 내재유전자를 특이적으로 증폭시킬 수 있는Primer(Pfru3-F/R)쌍을 이용한 PCR에서 95 bp의 PCR증폭 산물을 얻었으며, 들깨를 포함한 16개 작물에 대해 PCR을 수행한 결과에서 들깨만이 특이적으로 증폭되는 것을 확인하였다. 또한, 비타민 E 강화 유전자변형 들깨에 삽입된 TMT(${\gamma}$-tocopherol methyltransferase) 유전자와 OCS(Octopine synthase) terminator 연결 부위를 증폭시켜 148 bp의 PCR 산물을 얻을 수 있는 primer(TMTO-F/R)를 제작하였으며, 이러한 두 쌍의 primer를 이용하여 국내 개발된 비타민 E 강화 유전자변형 들깨의 PCR 정성 분석법을 확립하였다.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.106.2-106.2
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• 2007

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• BMB Reports
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• 제32권4호
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• pp.409-413
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• 1999

The cDNA encoding CMP-NeuAc:lactosylceramide ${\alpha}2$,3-sialyltransferase (GM3 synthase) was isolated from a human fetal brain cDNA library using sequence information obtained from amino acid sequences found in the conserved regions of the previously-cloned mouse GM3 synthase (mST3Gal V) and human sialyltransferases. The cDNA sequence included an open reading frame coding for 362 amino acids, and the primary structure of this enzyme predicted all the structural features characteristic of other sialyltransferases, including a type II membrane protein topology and both sialylmotifs. Comparative analysis of this cDNA with mST3Gal V showed 85% and 86% identity of the nucleotide and amino acid residues, respectively. The expression of this gene is highly restricted in both human fetal and adult tissues.

• BMB Reports
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• 제44권6호
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• pp.405-409
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• 2011

The present study demonstrated that valproic acid (VPA) transcriptionally regulates human GM3 synthase (hST3Gal V), which catalyzes ganglioside GM3 biosynthesis in ARPE-19 human retinal pigment epithelial cells. For this, we characterized the promoter region of the hST3Gal V gene. Functional analysis of the 5'-flanking region of the hST3Gal V gene revealed that the -177 to -83 region functions as the VPA-inducible promoter and that the CREB/ATF binding site at -143 is crucial for VPA-induced expression of hST3Gal V in ARPE-19 cells. In addition, the transcriptional activity of hST3Gal V induced by VPA in ARPE-19 cells was inhibited by SP600125, a c-Jun N-terminal kinase (JNK) inhibitor. In summary, our results identified the core promoter region in the hST3Gal V promoter and for the first time demonstrated that ATF2 binding to the CREB/ATF binding site at -143 is essential for transcriptional activation of hST3Gal V in VPA-induced ARPE-19 cells.

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.335-341
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• 2007

For the development of qualitative and quantitative PCR methods of genetically modified (GM) pepper developed in Korea, a capsanthin-capsorubin synthase (CCS) gene was used as the endogenous reference gene. The primer pair ccs-F/R amplifying the pepper endogenous gene gave rise to an amplicon of 102 bp. No amplified product was observed when DNA samples from 16 different plants were used as templates. The construct-specific primer pairs amplifying the junction region of the bar gene and Ti7 introduced in GM pepper gave rise to an amplicon of 182 bp. Quantitative PCR assay was performed using a TaqMan probe and a standard plasmid as a reference molecule, which contained both an endogenous and event-specific sequence. For the validation of this method, the test samples containing 0.1, 1, 3, 5, and 10% GM pepper were quantified.

• Food Science and Biotechnology
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• 제15권6호
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• pp.954-958
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• 2006

A comprehensive safety evaluation was conducted to assess the potential allergenicity of newly introduced proteins in genetically modified (GM) crops. We assessed the allergenicity of CP4 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in GM soybeans. This assessment was performed by IgE immunoblotting with soy-allergic children's sera, amino acid sequence homology with known allergens, and the digestibility of CP4 EPSPS. No differences in IgE-antigen binding by immunoblotting were found between GM soy samples and the corresponding non-GM samples. Based on the comparison of EPSPS amino acid sequence homology with current allergen databases, no known allergen was found. In addition, CP4 EPSPS protein was rapidly digested by simulated gastric fluid (SGF). Taken together, these results indicate that GM soybeans have no allergenicity in children and are as safe as conventional soybeans.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.106.1-106.1
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• 2007

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