• Environmental Analysis Health and Toxicology
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• v.18 no.4
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• pp.287-294
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• 2003

출아형 효모 Saccharomyces cerevisiae RAD3 유전자는 절제회복 및 세포의 생존에 필수적이며, DNA dependent ATPase와 DNA-RNA helicase활성을 가지고 있는 것으로 알려져 있다. 본 연구는 분열형 효모 Schizosaccharomyces pombe에서 절제회복과 세포의 생존에 필수적인 출아형 효모 RADS유전자와 유사한 유전자를 S. pombe genomic DNA library에서 분리하여 그 특성을 연구하였다. 분리한 RADS 유사유전자를 HRD3 유전자라 명명하였다. 발현 vector pET3a를 이용하여 분리한 HRD3 유전자를 과 발현하였을 때 HRD3단백질은 숙주단백질의 합성 억제 또는 분해 촉진을 유발하여 숙주세포인 대장균에 독성 효과를 나타냄이 관찰되었다. HRD3유전자와 lacZ유전자를 융합시킨 여러 가지 재조합 vector를 만들어 이들 융합단백질을 분리하였다. 이 결과 HRD3단백질의 카르복실 말단 부위가 DNA회복기능과 대장균에서의 독성효과를 나타내는 중요한 부위로 생각된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.37-71
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• 2021

Rapeseed is a typical winter crop, and its freezing stress tolerance is a major feature for winter survival. Therefore, it is important to comprehend clearly the physical and molecular mechanisms of rapeseed under freezing stress conditions. This study investigates the physical and transcriptome changes of two rapeseed lines, 'J8634-B-30' and 'EMS26', under cold acclimation and freezing temperature treatments. The proline content of 'J8634-B-30' at 5 ℃ increased 8.7-fold compared to that before treatment, and there was no significant change in that of 'EMS26' RNA-sequencing analysis revealed 5,083 differentially expressed genes (DEGs) of 'J8634-B-30' under cold acclimation condition. Among the genes, 2,784 (54.8%) were up-regulated and 2,299 (45.2%) were down-regulated. The DEGs of 'EMS26' under cold acclimation condition were 5,831 genes, and contained 2,199 up-regulated genes (37.7%) and 3,632 down-regulated genes (62.3%). Among them, only DEGs annotated in the cold response-related signaling pathways were selected, and their expression in the two rapeseed lines was compared. Comparative DEGs analysis indicated that cold response related signaling pathways are proline metabolism and ABA (Abscisic acid) signaling. And ICE (Inducer of CBF expression) - CBF (C-repeat-binding factor) - COR (Cold-regulated) signaling were the significantly differentially expressed transcripts in the two rapeseed lines. The major induced transcripts of 'J8634-B-30' induced P5CS (Δ'-pyrroline-5-carboxylate synthetase), which is related to proline biosynthesis, PYL (pyrabactin resistance-like protein, ABA receptor) and COR413 (cold-regulated 413 plasma membrane 1). In conclusion, these result provide a foundation for understanding the mechanisms of freezing stress tolerance in rapeseeds. Further functional studies should be performed on the freezing stress-related genes identified in this study, which can contribute to the transgenic and molecular breeding for freezing stress tolerance in rapeseed.

• Journal of Life Science
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• v.20 no.5
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• pp.729-735
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• 2010

In our previous study, it was reported that an herbal mixture, SH21B, inhibits fat accumulation and adipogenesis both in vitro and in vivo models of obesity. SH21B is a mixture composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd, and Nelumbo nucifera Gaertner (Ratio 3:3:3:3:3:2:2). The aim of this study was to investigate the detailed molecular mechanisms of the effects of SH21B on various regulators of the adipogenesis pathway. During the adipogenesis of 3T3-L1 cells, SH21B significantly decreased the expression levels of central transcription factors of adipogenesis, such as peroxisome proliferator-activated receptor (PPAR)$\gamma$ and CCAAT/enhancer binding protein (C/EBP)$\alpha$. To elucidate the detailed molecular mechanism of the anti-adipogenic effects of SH21B, we examined the expression levels of the various pro-adipogenic or anti-adipogenic regulators of adipogenesis upstream of $PPAR{\gamma}$ and C/$EBP{\alpha}$. The mRNA levels of Krox20 and Kruppel-like factor (KLF) 15, which are pro-adipogenic regulators, were significantly down-regulated by SH21B treatment, whereas the mRNA levels of C/$EBP{\gamma}$ and KLF5 were not changed. KLF2 and C/EBP homologous protein (CHOP), which are anti-adipogenic regulators, were significantly up-regulated by SH21B treatment. These results suggest that the molecular mechanism of the anti-adipogenic effect of SH21B involves both the down-regulations of pro-adipogenic regulators, such as Krox20 and KLF15, and the up-regulations of anti-adipogenic regulators, such as KLF2 and CHOP, which results in the suppression of central transcription factors of adipogenesis including $PPAR{\gamma}$ and C/$EBP{\alpha}$.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.304-313
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• 2004

Xylitol, a five-carbon natural sugar alcohol, is widely used non-cariogenic sugar substitute. In present study, the effects of xylitol on the expression of mRNA for glucosyltransferase which synthesizes glucan from sucrose were detected by Fluorescent in situ hybridization (FISH) and flow cytometry. FITC fluorescences for mRNA of gtfB, gtfC and gtfD were decreased further with increasing concentration of xylitol from 1% to 10% when detected by FISH. Flow cytometric analysis also showed that the expression of gtfB, gtfC and gtfD was increased by the addition of sucrose and decreased by the addition of xylitol to BHI broth containing 1% sucrose. In conclusion, the expression of gtfB, gtfC and gtfD mRNA was decreased by the addition of xylitol.

• Journal of Life Science
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• v.22 no.4
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• pp.492-498
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• 2012

To investigate whether phytochemicals affect cancer cell viability, human colorectal HCT116 cells were treated with four different phytochemicals. Among these phytochemicals, curcumin is the strongest inhibitor of cell proliferation. In addition, it decreased cell viability in a dose-dependent manner. To unveil the molecular mechanisms involved in the inhibition of cell proliferation by curcumin, we carried out oligo DNA microarray analysis. We found that 137 genes were up-regulated more than 2-fold, and 141 genes were down-regulated more than 2-fold by 25 ${\mu}M$ curcumin treatment. Among the up-regulated genes, we selected 3 genes (ATF-3, GADD45A, and NR4A1) to confirm microarray data. The results of RT-PCR strongly agreed with those of the microarray data. Among the phytochemicals used in this study, curcumin is the strongest inducer of ATF3 expression, and increased ATF3 expression in a dose-dependent manner. Interestingly, FACS analysis showed that the inhibition of cell growth by curcumin was recovered by ATF3-siRNA transfection. Finally, we detected the changes of gene expression by ectopic expression of ATF3. The results indicated that many up-regulated genes were related to apoptosis. Overall, these results suggest that ATF3 may play an important role in the anti-proliferative activity of curcumin in human colorectal cancer cells.

• Korean Journal of Veterinary Research
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• v.42 no.4
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• pp.505-512
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• 2002

대장균 K99 섬모의 생합성은 8개로 구성된 K99의 특이 유전자의 발현과 숙주유래 인자에 의해 조절되는 다른 유전자들의 발현에 의존된다. 본 연구에서는 K99섬모 유전자군중 제 3지역 발현에 유전조절자의 관련성 여부를 연구하였다. Gel retardation 분석 방법올 통하여 제3지역의 발현에 관련된 유전조절단위를 함유한 fanF 지역의 단백질 인자가 부착됨을 암시하였다. 이 분석방법을 이용한 결과는 또한 이 단백질 인자가 K99 유전자에서 유래되지 않고 대장균 염색체에서 유래됨을 지적하였다. 이를 보다 더 조사하기 위하여 대장균 염색체에 Tn10 transposon 유전자 변이 실험을 수행하였다. K99 유전자군으로부터 제 1지역과 제2지역의 유전자를 제거시키고, 제 3지역의 유전자인 fanG에 transposon TnlacZ를 삽입한 pTL65-1 plasmid을 제작하였다. 이 pTL65-1는 다시 Tn10으로 염색체가 변이된 대장균에 주입하였다. 3개의 pTL65-1 주입된 Tn10 대장균 변이체 내에서 fanG의 발현이 증가되었다. 이들 변이대장균으로부터 Tn10이 어떤 염색체 유전자 부위를 변이 시켰는지 확인하기 위해서 변이부위 유전자를 cloning하여 염기서열을 분석하였다. 이중 2개의 clone이 동일하였으며 지금까지 알려지지 않은 유전자였다. 이들 2개의 변이체 내에서 fanG의 발현은 대조군과 비교해 약 4.2배 증가 되였다. 결론적으로 이들 2개의 clone으로부터 유래된 인자는 지금까지 알려지지 않은 제 3지역의 억제 조절자임을 나타내었다.

• Development and Reproduction
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• v.4 no.2
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• pp.221-229
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• 2000

Lactogenesis in mammary gland is under the control of various lactogenic hormones including hypophysial growth hormone and prolactin. Recent studies reported that such pituitary lactogenic hormones are also expressed in mammary cells as well as in pituitary. For the purpose to analyze the role of these non-pituitary hormones in mammary cells, $\beta$ -lactoglobulin (BLG) gene promoter was selected as a model system. The growth hormone suppressed BLG promoter activity when it was applied alone on cultured mammary HCll cells. Along with lactogenic hormones such as insulin, prolactin and glucocorticoid, however, it significantly enhanced expression of BLG promoter activity in a dosage- dependent manner. Exogenous expression of the growth hormone gene in cultured mammary cells also strongly promoted cell proliferation and BLG promoter activity. Bovine growth hormone promoter, on the contrary, did not revealed any notable activity. Above results suggest that endogenous expression of the pituitary hormone genes in mammary cells is not a regulation leakage but a physiological control. Moreover, artificial overproduction of the growth hormone in mammary gland may help increase milk production.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.802-808
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• 2005

Human Disabled-2 (Dab2) is a candidate tumor suppressor gone that regulates cell growth by c-Fos suppression in normal cells. In many cancer cells, Dab2 expression is lost or greatly diminished in $\∼85\%$ of the breast and ovarian cancers. In this study, we have examined the methylation status of CpG island on Dab2 gene promoter using bisulfite-assisted genomic sequencing and methylation specific PCR (MSP) method in human breast cancer cell line, MDA MB-231 cells. In normal human uterus endometrial cells, Dab2 was completely unmethylated. In contrast, Dab2 was methylated on CpG dinucleotides near the TATA_ box in MDA MB-231 cells. following MDA MB-231 cells by treatment with 5-azacytidine, Dab2 gene were demethylated and reexpressed. Result of this study suggested that silencing of Dab2 gene is correlated to CpG island methylation in human breast cancer cell line, MBA MD-231 cells.

• Environmental Analysis Health and Toxicology
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• v.24 no.4
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• pp.321-332
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• 2009

본 연구의 목적은 다이아지논(Diazinon; O, O-diethyl O-[6-methyl-2 (1-methylethyl)-4-pyrimidinyl] phosphorothioate)에 노출된 모델 생물체(송사리)의 행동변화와 관련된 분자생물학적 기전 규명을 통하여 비정상적 행동의 모니터링을 위한 생물지표(biomarker)를 개발하는데 있다. 이를 위해 우선 suppression subtractive hybridization (SSH) 및 DNA microarray 기법을 활용하여 다양한 유전자를 스크리닝하였다. 다이아지논에 노출시킨 송사리에서 발현의 차이가 나는 상향 조절된 유전자 97개 (알려지지 않은 유전자 27개 포함)와 하향 조절된 유전자 99개 (알려지지 않은 유전자 60개 포함)를 동정 하였고 이들 중 이상행동과 관련되는 것으로 보이는 유전자 10개 (상향조절 5개, 하향조절 5개)를 선발하였다. 이들 중에서 primer 제작이 잘된 beta-1, Orla C3-1, parvalbumin 및 apolipoprotein E을 선발하여 그 유전자 발현을 real-time PCR 기법을 사용하여 정량적으로 모니터링 하였다. Orla C3-1, parvalbumin 및 apolipoprotein E는 고농도의 다이아지논 처리(1000 ppb; 24 h)에서 그 발현이 억제됨이 관찰되었다. 다이아지논 처리 시 신경질환 (알츠하이머 병 및 다운신드롬)에 관련된 apolipoprotein E와 근육세포의 유연화에 작용하는 parvalbumin 등의 발현억제는 송사리의 인지능력 교란 및 근육세포의 경직 등을 각각 유도하여 송사리의 비정상적 행동을 야기하는 것으로 판단되었다. 따라서 이들 생물지표는 신경독성물질에 의한 송사리 및 기타 어류의 이상행동의 변화의 감지에 활용될 수 있을 것으로 사료된다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.1-8
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• 2006

To develop a new variety of orchardgrass with improved digestibility, caffeic acid O-methyltransferase (Dgcomt), which is a methylation enzyme involved in the early stages of lignin biosynthesis, was isolated and characterized. Dgcomt was expressed not only in leaves but also in stems and roots. The expression levels of transcripts were high in stems and roots which are the most lignified tissues, and only moderate levels of transcripts were expressed in leaves. To develop transgenic orchardgrass plants by down-regulating the Dgcomt gene, an RNAi suppression vector with partial Dgcomt DNA fragment was constructed and transferred into the genome of orchardgrass via Agrobacterium-mediated gene transfer method. PCR and Southern blot analyses with genomic DNAs from putative transgenic plants revealed that the T-DNA region containing RNAi construct was successfully integrated into the genome of orchardgrass. Northern blot analysis revealed that the majority of the down-regulated transgenic lines showed significant reduction in Dgcomt gene expression. These RNAi transgenic orchardgrass will be useful for molecular breeding of new variety with improved digestibility by down-regulating lignin biosynthetic enzyme.