• Archives of Pharmacal Research
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• v.16 no.4
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• pp.289-294
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• 1993

A binding protein of radio-labeled sanjoinine-A (fangufoline) in rat brain cytoplasm was investigated, using an equilibrium dialysis technique. The labeled agent was bound to the cytosol fraction with two distinctly different types of sets in calclum ion-dependent manner. The bound protein was identified as calmodulin by dgel filtration of the sanjoinine-A bound cytosol fraction on a Sephadex G-75 column. Calmodulin was bound to sanjoinine-A bound at two sets of binding sites in the calculated as two at high affinity sites $(Kd=1.1\;mu{M)}$ and four at low affinity sites $(Kd=3.1\;\mu{M)}$.

• Journal of Plant Biology
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• v.33 no.1
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• pp.81-84
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• 1990

The chloroplast has been the prime light-energy harvesting organelle on earth. It also carries out several key metabolic processes, such as lipid synthesis and nitrogen metabolism. Even though the chloroplast has its own genome, its coding capacity can afford only dozens of proteins, and most of the proteins functioning in the chloroplast are imported from the cytosol where nuclear encoded chloroplast genes are synthesized on free cytosokic ribosomes. Precursor proteins synthesized on cytosolic ribosomes have transit peptides at the amino termini of the proteins, and the transit peptide is sufficient to transfer chloroplast proteins from the cytosol into the chloroplast. When comparing amino acid sequences duduced from the nucleotide sequences of the clones of the chloroplast proteins, high homologies can be found among the transit peptides of proteins with the same function. Overall amino acid compositions of the transit peptides show amphiphilic characters of the transit peptides, and the amphiphilicity indicates that three dimensional structure of the transit peptide is responsible for the translocation of the chloroplast proteins.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.146-146
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• 2002

• Molecules and Cells
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• v.19 no.2
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• pp.268-278
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• 2005

We investigated the effect of cytosolic and extracellular $Ca^{2+}$ on $Ca^{2+}$ signals in pancreatic acinar cells by measuring $Ca^{2+}$ concentration in the cytosol($[Ca^{2+}]_c$) and in the lumen of the ER($[Ca^{2+}]_{Lu}$). To control buffers and dye in the cytosol, a patch-clamp microelectrode was employed. Acetylcholine released $Ca^{2+}$ mainly from the basolateral ER-rich part of the cell. The rate of $Ca^{2+}$ release from the ER was highly sensitive to the buffering of $[Ca^{2+}]_c$ whereas ER $Ca^{2+}$ refilling was enhanced by supplying free $Ca^{2+}$ to the cytosol with $[Ca^{2+}]_c$ clamped at resting levels with a patch pipette containing 10 mM BAPTA and 2 mM $Ca^{2+}$. Elevation of extracellular $Ca^{2+}$ to 10 mM from 1 mM raised resting $[Ca^{2+}]_c$ slightly and often generated $[Ca^{2+}]_c$ oscillations in single or clustered cells. Although pancreatic acinar cells are reported to have extracellular $Ca^{2+}$-sensing receptors linked to phospholipase C that mobilize $Ca^{2+}$ from the ER, exposure of cells to 10 mM $Ca^{2+}$ did not decrease $[Ca^{2+}]_{Lu}$ but rather raised it. From these findings we conclude that 1) ER $Ca^{2+}$ release is strictly regulated by feedback inhibition of $[Ca^{2+}]_c$, 2) ER $Ca^{2+}$ refilling is determined by the rate of $Ca^{2+}$ influx and occurs mainly in the tiny subplasmalemmal spaces, 3) extracellular $Ca^{2+}$-induced $[Ca^{2+}]_c$ oscillations appear to be triggered not by activation of extracellular $Ca^{2+}$-sensing receptors but by the ER sensitised by elevated $[Ca^{2+}]_c$ and $[Ca^{2+}]_{Lu}$.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.85-85
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• 2003

한우 난소의 황체는 다양한 세포들로 구성되어 있으며 난소의 생식기능유지와 임신유지에 중요한 인자가 복잡하게 관련되어 있으며 이들 황체에서 분비하는 단백질은 황체기능에 필수적으로 중요한 작용을 한다. 본 연구는 난소의 황체일령에 따른 단백질 분비 패턴을 조사함으로써 황체세포의 기능과 임신 유지에 관련되는 인자들을 조사하기 위하여 수행하였다. 한우에서 채취한 난소에서 황체를 분리, 황체시기별(전기, 중기, 말기)로 구분하여 cytosol을 분리 정제하였다. 황체시기별로 분리된 황체 단백질의 성분을 분석하기 위해 ion-exchange chromatography를 이용하여 단백질 패턴을 조사, 추출된 fraction을 단백질 정량후 SDS-PAGE를 실시하였다. 그 결과 중기에서의 단백질의 농도가 가장 높았으며, 특히 단백질 패턴 또한 다른 양상을 보였다. 시기별로 구분한 각각의 fraction을 SDS-PAGE로 조사했을 때 중기와 말기황체 cytosol의 fraction 3번과 4번에서 다른 양상을 보였으며 SDS-PAGE에서 120kb, 95kb, 34kb, 25kb 등의 단백질 밴드를 확인할 수 있었다. 초, 중기황체에서만 특이하게 검출되는 단백질 band를 확인할 수 있었으며 이 들 단백질을 구체적으로 확인하기 위하여 Two-Dimensional electrophoresis를 이용하여 실험을 수행하였다. 시기별로 분리된 황체를 일반적인 IEF단백질 분리법으로 cytosol을 회수한 후 IPG-system을 이용하여 1차원 전기영동을 한 후, SDS-PAGE로 이차원 전기영동을 실시하였다. 이차원 전기영동 결과, SDS-PAGE의 결과와 비슷한 위치에 부분적으로 다른 spot의 양상을 보였다. 특히 기능황체에서의 특이적 발현 spot을 확인할 수 있었다. 이러한 결과들로부터 황체의 progesterone분비기능의 역할을 수행하기 위한 단백질들이 전, 중기에 발현된다는 것을 알 수 있고 퇴행황체에서는 발현이 안되고 있는 것을 알 수 있다. 이러한 결과를 토대로 다른 양상을 띤 spot을 분리하여 어떤 단백질인지를 분석하여 각각의 황체단백질의 특성을 규명할 수 있을 것으로 사료된다.

• Journal of Ginseng Research
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• v.17 no.2
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• pp.114-122
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• 1993

0.5 mg of natural ginsenoside mixture and 0.8 $\mu$Ci of synthesized 14C-ginsenosides were administered orally to a rat and killed at one hour after the ginsenoside administration and the liver was fractionated into nuclear fraction, mitrochondria microsomes and cytosol fraction. Radioactivity distribu lion in subcellular fractions of the liver showed that 32o1c of total radioactivity absorbed in the liver was in cytosol fraction but a significant portion of the radioactivity was also found in mitochondria (26.6%) and microsomal fraction (18.l%). 5.8% of the total radioactivity was recovered from the nuclear fraction as well. This suggested that ginsenosides might be distributed into all subcellular fractions. Activities of mitochondrial aldehyde dehydrogenase, lactate dehydrogenase and malate dehydrogenase of the liver of rat at two hours after the ginsenoside administraion were found appreciably stimulated, suggesting that the ginsenoside concentration in the liver might be around 10-5%, since optimum concentrations for most enzyme catalyzed reactions in vitro were known to be 10-6% 10-4%. A significant portion of the radioactivity recovered from subcellular fractions of the liver was found in protein fractions, suggesting that proteins might interact with ginsenosides. Examination of protein-ginsenoside interation by gel filtration, equilibrium dialysis and amonium sulfate precipitation technique suggesting that proteins and ginsenosides do not bound covalently but weakl\ulcorner combined. When purified ginsenoside Rbl and Rgl were incubated with rat liver cytosolic enzymes for 20 min, the above ginsenosides were hydrolyzed quickly, suggesting that ginsenosides might be rapidly hydrolyzed and metabolized in the liver. It was also observed in vitro that the ginsenosides such as Rbl and Rgl were easily hydrolyzed by rat liver cytosol preparation suggesting that absorbed ginsenosides might be quickly hydrolyzed and metabolized in the liver.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.149-149
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• 2017

The RING (Really Interesting New Gene) finger proteins are known to play crucial roles in various abiotic stresses in plants. In this study, we report on RING finger E3 ligase, ${\underline{O}ryza}$ ${\underline{s}ativa}$ ${\underline{s}alt$-, ${\underline{A}BA}$- and ${\underline{d}rounght}$ stress-${\underline{i}nduced}$ RING finger ${\underline{p}}rotein{\underline{1}}$ gene (OsSAD1). In vitro ubiquitination assay demonstrated that unlike OsSAD1, a single amino acid substitution ($OsSAD1^{C168A}$) of the RING domain showed no E3 ligase activity, supporting the notion that the activity of most E3s is specified by a RING domain. Result of Yeast-Two hybridization, In vivo protein degradation assay supports that OsSAD1 interacting with 3 substrate, OsSNAC2, OsGRAS44 and OsPIRIN1, and mediates proteolysis of 3 substrates via the 26S proteasome pathway. Subcellular localizations of OsSAD1 while approximately 62% of transient signals were detected in cytosol, 38% of signals were showed nucleus. However, transiently expression of OsSAD1 was detected in cytosol 30% while as 70% of nucleus under 200 mM salt treated rice protoplasts. Results of bimolecular fluorescence complementation (BiFC) showed that two nucleus-localized proteins (OsSNAC2 and OsGRAS44) interacted with OsSAD1 in the both cytosol and nucleus. Heterogeneous overexpression of OsSAD1 Heterogeneous overexpresssion of OsSAD1 in Arabidopsis exhibited sensitive phenotypes with respect to Salt-, mannitol-responsive seed germination, seedling growth. In ABA conditions, OsSAD1 overexpression plants showed highly tolerance phenotypes, such as root length and stomatal closure. Our findings suggest that the OsSAD1 may play a negative regulator in salt stress response by modulating levels of its target proteins.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.1948-1956
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• 2020

Objective: The purpose of this study was to reveal the metabolic shift in the fungus cocultured with the methanogen (Methanobrevibacter thaueri). Methods: Gas chromatography-mass spectrometry was used to investigate the metabolites in anaerobic fungal (Pecoramyces sp. F1) cells and the supernatant. Results: A total of 104 and 102 metabolites were detected in the fungal cells and the supernatant, respectively. The partial least squares-discriminant analysis showed that the metabolite profiles in both the fungal cell and the supernatant were distinctly shifted when co-cultured with methanogen. Statistically, 16 and 30 metabolites were significantly (p<0.05) affected in the fungal cell and the supernatant, respectively by the co-cultured methanogen. Metabolic pathway analysis showed that co-culturing with methanogen reduced the production of lactate from pyruvate in the cytosol and increased metabolism in the hydrogenosomes of the anaerobic fungus. Citrate was accumulated in the cytosol of the fungus co-cultured with the methanogen. Conclusion: The co-culture of the anaerobic fungus and the methanogen is a good model for studying the microbial interaction between H₂-producing and H₂-utilizing microorganisms. However, metabolism in hydrogenosome needs to be further studied to gain better insight in the hydrogen transfer among microorganisms.

• Journal of Life Science
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• v.10 no.6
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• pp.570-576
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• 2000

This study was designed to investigate the effects of mulberry (Morus alba L.) leaf extract (MLE) on oxygen radicals and their scavenger enzymes in brain membranes of rats. Sprague-Dawley (SD) male rats (160$\pm$10 g) were fed basic diet (control group), and experimental diets (MLE-100 and MLE-300 groups) added 100 and 300 mg/kg BW/day for 6 weeks. Hydroxyl radical (.OH) lecels resulted in significant decreases (13.4% and 21.1%, 12.0% and 13.4%, respectively) in brain mitochondria and microsome of MLE-100 and MLE-300 groups compared with control group. Superoxide radical ($O_2$) levels were significantly decreased about 12% in brain cytosol of MLE-300 group compared with control group. Lipid peroxide (LPO) levels were effectively inhibited (18.1% and 12.3%, respectively) in brain mitochondria and microsomes of MLE-300 groups compared with control group. Oxidized protein (OP) levels were significantly decreased (14.2%, and 10.9%, respectively) in brain mitochondria and microsomes of MLE-300 groups compared with control group. Mn-SOD activities in brain mitochondria were significantly increased (13.5% and 18.6%, respectively) in MLE-100 and MLE-300 groups, and Cu/Zn-SOD activities in brain cytosol were also effectively increased (about 17.7%) in MLE-300 groups compared with control group. GSHPx activities in brain cytosol were remarkably increased (17.2% and 23.9%, respectively) in MLE-100 and MLE-300 groups compared with control group. These results suggest that anti-aging effect of mulberry leaf extract (MLE) may play a pivotal role in attenuating a various age-related changes in brain.

• Journal of Life Science
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• v.10 no.4
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• pp.340-346
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• 2000

This study was designed to investigate the effects of silk fibroin(Mw 500) powder (SFP) on oxygen radicals and the scavenger enzymes in brain membranes of rats. Spragu-Dawley(SD) male rats(160${\pm}$10g) were fed basic diet(control group), and experimental diets(SFP-2.5 and SFP-5.0 groups) added 2.5 and 5.0g/kg BW/day for 6 weeks. Hydroxyl radical($.$OH) levels resulted in a decreases(6.6% and 9.7%, 2.8% and 11.9%, respectively) in brain mitochondria and microsomes of SFP-2.5 and SFP-5.0 groups compared with control group, but were significantly decreased in these membrances of SFP-5.0 group only. Superoxide radical (O2) levels were a slightly decreased (2.0% and 9.1%, respectively) in brain cytosol of SFP-2.5 and SFP-5.0 groups compared with control group. Lipid peroxide(LPO) levels were significantly decreased (12.9% and 21.9%, 13.2% and 22.5%, respectively) in brain mitochondria and microsomes of SFP-2.5 and SFP-5.0 groups compared with control group. Oxidized protein (OP) levels were significantly decreased (16.7% and 15.7%, respectively) in brain microsomes of SFP-2.5 and SFP-5.0 group compared with control group, but significantly difference between in brain mitochondria of these two groups could not be obtained. Mn-SOD activities were remarkably increased (11.2% and 24.2%, respectively) in mitochodria of SFP-2.5 and SFP-5.0 groups. CuZn-SOD activities were effectively increased (7.7% and 19.6%, respectively) in brain cytosol of SFP-2.5 and SFP-5.0 groups, but significant difference between control and SFP-2.5 groups could be not obtained. GSHPx activities were considerably increased (5.3% and 11.7%, respectively) in brain cytosol of SFP-2.0 and SFP-5.0 groups compared with control group. There results suggest that anti-aging effect of silk fibroin may play an effective learning and memory role in a attenuating a oxidative stress and increasing a scavenger enzyme activity in brain membranes.