• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.535-539
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• 2005

The thermoacidophilic archaeon Thermoplasma acidophilum has long been known to utilize D-glucose via the non-phosphorylated Entner-Doudoroff (nED) pathway. We now report the identification of a gene encoding 2-keto-3-deoxy-D-gluconate (KDG) kinase. The discovery of this gene implies the presence of a glycolysis pathway, other than the nED pathway. It was found that Ta0122 in the T. acidophilum genome corresponded to KDG kinase. This enzyme shares no similarity with known KDG kinases, and belongs to a novel class of sugar kinases. Of the five sugars tested only KDG was utilized as a substrate.

• Molecules and Cells
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• 제37권3호
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• pp.248-256
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• 2014

N-acetylglucosamine kinase (GlcNAc kinase or NAGK; EC 2.7.1.59) is a N-acetylhexosamine kinase that belong to the sugar kinase/heat shock protein 70/actin superfamily. In this study, we investigated both the expression and function of NAGK in neurons. Immunohistochemistry of rat brain sections showed that NAGK was expressed at high levels in neurons but at low levels in astrocytes. Immunocytochemistry of rat hippocampal dissociate cultures confirmed these findings and showed that NAGK was also expressed at low levels in oligodendrocytes. Furthermore, several NAGK clusters were observed in the nucleoplasm of both neuron and glia. The overexpression of EGFP- or RFP (DsRed2)-tagged NAGK in rat hippocampal neurons (DIV 5-9) increased the complexity of dendritic architecture by increasing the numbers of primary dendrites and dendritic branches. In contrast, knockdown of NAGK by shRNA resulted in dendrite degeneration, and this was prevented by the co-expression of RFP-tagged NAGK. These results suggest that the upregulation of dendritic complexity is a non-canonical function of NAGK.

• 한국당과학회:학술대회논문집
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• 한국당과학회 2006년도 제1회 연례학술대회
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• pp.32-32
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• 2006

• Molecules and Cells
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• 제39권9호
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• pp.669-679
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• 2016

N-acetyl-D-glucosamine kinase (GlcNAc kinase or NAGK) primarily catalyzes phosphoryl transfer to GlcNAc during amino sugar metabolism. Recently, it was shown NAGK interacts with dynein light chain roadblock type 1 (DYNLRB1) and upregulates axo-dendritic growth, which is an enzyme activity-independent, non-canonical structural role. The authors examined the distributions of NAGK and NAGK-dynein complexes during the cell cycle in HEK293T cells. NAGK was expressed throughout different stages of cell division and immunocytochemistry (ICC) showed NAGK was localized at nuclear envelope, spindle microtubules (MTs), and kinetochores (KTs). A proximity ligation assay (PLA) for NAGK and DYNLRB1 revealed NAGK-dynein complex on nuclear envelopes in prophase cells and on chromosomes in metaphase cells. NAGK-DYNLRB1 PLA followed by Lis1/NudE1 immunostaining showed NAGK-dynein complexes were colocalized with Lis1 and NudE1 signals, and PLA for NAGK-Lis1 showed similar signal patterns, suggesting a functional link between NAGK and dynein-Lis1 complex. Subsequently, NAGK-dynein complexes were found in KTs and on nuclear membranes where KTs were marked with CENP-B ICC and nuclear membrane with lamin ICC. Furthermore, knockdown of NAGK by small hairpin (sh) RNA was found to delay cell division. These results indicate that the NAGK-dynein interaction with the involvements of Lis1 and NudE1 plays an important role in prophase nuclear envelope breakdown (NEB) and metaphase MT-KT attachment during eukaryotic cell division.

• 동아시아식생활학회지
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• 제27권1호
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• pp.1-8
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• 2017

This study was conducted to investigate alterations of seaweed composition upon Lactobacillus rhamnosus GG (LGG) fermentation as well as potential anti-inflammatory effects and mechanism (s) of water extracts and fermented water extracts of Laminaria japonica (LJ) and Hizikia fusiforme (HF) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Total polyphenol, total sugar, and reducing sugar contents were measured in LJ and HF water extracts before and after fermentation by LGG. Alterations of inflammatory cytokine levels in cell culture media were measured by ELISA, and levels of phosphorylation of c-jun NH2-terminalkinase (JNK) and extra cellular signal regulated kinase (ERK) were examined by Western blot analysis. LGG fermentation of LJ and HF altered total polyphenol and sugar contents in water extracts of LJ and HF. LPS-induced production of pro-inflammatory cytokines such as IL-6 and $TNF-{\alpha}$ was significantly reduced by HF-f compared to control in RAW264.7 cells. Consistent with reduction of anti-inflammatory cytokine, interleukin (IL)-6, and tumor necrosis factor $(TNF)-{\alpha}$ levels by HF-f, HF-f also significantly reduced phosphorylation of ERK and JNK in LPS-stimulated RAW264.7 cells. In addition, LJ-f and HF also significantly reduced phosphorylation of JNK and ERK induced by LPS in RAW264.7 cells. Overall, our result suggests that HF-f among the four tested seaweed extracts is the most potent anti-inflammatory agent, and its mechanism of action is partially mediated by reduction of JNK and ERK phosphorylation as well as IL-6 and $TNF-{\alpha}$ production in LPS-stimulated RAW264.7 cells.

• 대한핵의학회지
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• 제36권4호
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• pp.209-223
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• 2002

By considering the biological properties of a tumor, it should be possible to realize better results in cancer therapy. PET imaging offers the opportunity to measure tumor growth non-invasively and repeatedly as an early assessment of response to cancer therapy. Measuring cellular growth instead of energy metabolism showed offer significant advantages in evaluating therapy. Thymidine and its derivative nucleoside compounds can be changed to mono, di- and tri- phosphate compounds by thymidine kinase and then be incorporated into DNA. Their bindings are increased in highly proliferating cells due to the high DNA synthesis rate. To evaluate cell proliferation, many kinds of thymidine and uridine derivatives have been labeled with positron emitter and radioactive iodine. Compared to radiopharmaceuticals which have radioisotope labeled base ring such as pyirmidine, the radiopharmacuticals which have radioisotope labeled sugar ring are more stable in vivo and have metabolic resistance. The biological properties such as DNA incorporation ratios are highly dependent on their chemical structures and metabolic processes. This overview describes synthesis of radiopharmaceuticals and their biological properties for imaging of tumor cell proliferation.

• 한국식품영양과학회지
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• 제46권6호
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• pp.671-680
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• 2017

본 연구 결과 검은콩 물 에탄올 추출물과 Lactobacillus rhamnosus GG(LGG)와 Bifidobacterium animals subsp. lactis BB-12(BB-12)를 이용하여 발효시킨 발효검은콩 물 에탄올 추출물의 발효 전과 후의 성분변화를 분석하고, 검은콩과 검은콩 발효 추출물이 모유두 세포 성장에 미치는 효과를 알아보기 위해 primary 인간 모유두 세포(HFDPC)에 검은콩 추출물(BWE, BEE)과 발효검은콩 추출물(BWE-F, BEE-F)을 다양한 농도로 처리하여 세포독성을 확인하였으며, 이를 바탕으로 적정 처치 농도를 결정하여 모발 성장촉진(VEGF와 KGF/FGF7)과 억제($TGF-{\beta}1$과 AR)에 관여하는 유전자 발현을 mRNA 수준에서 확인하였다. 나아가 검은콩 추출물이 HFDPC의 생존 촉진에 미치는 영향을 Akt와 Erk의 인산화 활성을 통해 비교 분석하였다. LGG와 BB-12를 이용하여 발효시킨 검은콩은 발효가 진행됨에 따라 pH, 총폴리페놀, 총당 환원당의 함량이 감소하였으며, 검은콩 4종 추출물(BWE, BEE, BWE-F, BEE-F) 중 BWE, BEE, BWE-F가 VEGF의 mRNA 발현을 증가시키고, 모든 처리군에서 KGF/FGF7의 mRNA 발현을 유의적으로 증가시킴을 확인할 수 있었다. 나아가 BWE, BEE, BWE-F가 Erk의 활성을 증가시켰음을 확인할 수 있었다. 따라서 검은콩 물 추출물과 검은콩 에탄올 추출물, 그리고 발효검은콩 물 추출물이 인간 모유두 세포의 세포성장에 모발 성장 촉진인자의 활성과 Erk의 활성화 등을 통한 기전으로 긍정적인 영향을 미침으로써 모발 성장 및 모발 건강을 위한 기능성원료로서의 가능성을 확인할 수 있었으며, 유산균 2종(LGG, BB-12)을 이용한 발효검은콩이 검은콩과 비교하여 모발 성장 촉진 관련 단백질 발현에서는 유의적인 우월성을 가지지는 않음을 확인하였다. 추후 다른 유산균 균 총을 이용한 발효검은콩의 연구와 더불어 보다 정밀한 발효를 통한 검은콩 추출물의 성분과 조성의 변화를 바탕으로 한 모발 성장 및 모주기 관련 연구가 이루어져야 할 것이라 생각된다.

• Journal of Plant Biotechnology
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• 제36권1호
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• pp.23-29
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• 2009

벼의 저온처리 cDNA 은행에서 분리된 CCCH 형태 zinc finger 단백질인 OsZF2의 기능을 분석하기 위하여 벼에서 CaMV 35S 프로모터 조절하에 OsZF2가 발현(35S:OsZF2)되는 형질전환벼 식물체를 개발하였다. 35S:OsZF2 형질전환벼에 대한 하이그로 마이신저항성 검정을 통해 동형접합체 계통을 선발하고 Northern 발현분석에 의해 OsZF2 유전자가 형질전환체에서 과발현되는 것을 확인하였다. 형질전환체와 대조구인 낙동벼를 100 mM NaCl 첨가 MS 배지에서 키운 후 잎과 뿌리의 길이를 측정하여 내염성 검정을 수행한 결과 대조구에 비해 형질전환체 생육이 다소 양호 한 것으로 나타났다. GMO 포장에서 생육상태를 관찰 한 결과 형질전환체는 생육지연으로 인한 왜화 현상을 나타내며 출수기 또한 열흘 정도 지연되나 등숙기에는 대조구와 같은 초장을 보였다. zinc finger 유전자는 식물체의 발달과 분화 단계 및 환경 스트레스 반응 등 중요한 역할을 하는 것으로 알려져 있으므로 유전체발현 분석으로 하위단계에서 조절되는 유전자 발현 양상을 분석하였다. 35S:OsZF2 전환체에서 낙동벼보다 4배 이상 발현이 증가된 유전자 중에서 게놈 주석에 기초한 기능을 유추하면 신호전달과 관련된 protein kinase, DNA 결합단백질과 대사에 관련된 효소 유전자, 스트레스 반응에 관여하는 일부 유전자 및 병 저항성과 관련된 유전자들의 발현이 증가되었다. 따라서 벼에서 분리된 OsZF2 CCCH type zinc finger 유전자는 벼 성장 발달과 스트레스에 반응하는 상위 조절자로서 기능을 할 것으로 추측된다.

• 생명과학회지
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• 제31권8호
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• pp.729-735
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• 2021

제 2 형 당뇨병은 조직의 포도당 흡수 능력에 이상이 있을 때 발생하며, 인슐린에 의한 포도당 섭취와 신진대사는 혈당을 유지하는 기본 활동이며 포도당 섭취는 인슐린이 세포 표면의 수용체에 결합하여 시작되는 다양한 신호 단계를 거친다. 본 연구는 Ecklonia cava에서 분리된 활성 화합물 인 2,7-phloroglucinol-6,6-bieckol이 3T3-L1 지방 세포에서 인슐린 신호전달체계에 따른 포도당 흡수 증가에 미치는 영향에 대한 것이다. 2,7-phloroglucinol-6,6-bieckol 은 3T3-L1 지방 세포에서 농도의존적으로 GLUT4의 발현을 증가시켜 원형질막에서의 glucose uptake 를 증가시켰다. 이는 인슐린 신호 전달 경로에서 2,7-phloroglucinol-6,6-bieckol 에 의한 IRS-1, AKT의 인산화 및 PI3K 활성화에 의한 것이다. PHB는 또한 AMPK 인산화와 활성화를 자극했다. 2,7-phloroglucinol-6,6-bieckol에 의한 PI3K/AKT 및 AMPK 경로의 인산화 및 활성화는 wortmannin (PI3K 억제제) 및 화합물 C (AMPK 억제제)를 사용하여 확인하였다. 본 연구에서 2,7-phloroglucinol-6,6-bieckol 이 3T3-L1 지방 세포에서 PI3K 및 AMPK 경로를 통해 원형질막으로의 GLUT4 전위를 촉진함으로써 포도당 흡수를 증가시킬 수 있음을 나타내었다. 이러한 결과는 2,7-phloroglucinol-6,6-bieckol 가 인슐린 감수성을 개선하는 데 도움이 될 수 있음을 시사한다.

• Toxicological Research
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• 제23권2호
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• pp.127-133
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• 2007

Metformin is a drug used to lower blood sugar levels in patients with type 2 diabetes via activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK). The primary objective of this study was to investigate whether metformin at the pharmacologically effective concentrations affects the expressions of ${\gamma}$-glutamylcysteine synthetase and phase II antioxidant genes in the H4IIE cell. Treatment of the cells with either metformin or 5-aminoimidazole-4-carboxamide riboside (AICAR) abrogated tert-butylhydroxyquinone (t-BHQ) induction of ${\gamma}$-glutamylcysteine synthetase, a rate limiting enzyme of GSH synthesis. The ability of t-BHQ to induce glutathione S-transferases (GSTs), a major class of phase II detoxifying enzymes that playa critical role in protecting cells from oxidative stress or electrophiles, was also inhibited by the agents. Transcriptional gene repression by metformin was verified by the GSTA2 promoter luciferase assay. Moreover, either metformin or AICAR treatment significantly decreased t-BHQ-dependent induction of other GSTs (i.e., $GST{\mu}$ and $GST{\pi}$ forms). Taken together, our data indicate that metformin treatment may result in the repression of ${\gamma}$-glutamylcysteine synthetase and glutathione S-transferase genes possibly via AMPK activation.