• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.109-114
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• 2007

Sar1p is a ras-related GTP-binding protein that functions in intracellular protein transport between the endoplasmic reticulum (ER) and the Golgi complex. The effector domain of Ras family proteins is highly conserved and this domain is functionally interchangeable in plant, yeast and mammalian Sar1. Using a recombinant Brassica sar1 protein (Bsar1p) harboring point mutations in its effector domain, we here investigated the ability of Sar1p to bind and hydrolyze GTP and to interact with the two sar1-specific regulators, GTPase activating protein (GAP) and guanine exchange factor (GEF). The T51A and T55A mutations impaired Bsar1p intrinsic GTP-binding and GDP-dissociation activity. In contrast, mutations in the switch domain of Bsar1 did not affect its intrinsic GTPase activity. Moreover, the P50A, P54A, and S56A mutations affected the interaction between Bsar1p and GAP. P54A mutant protein did not interact with two regulating proteins, GEF and GAP, even though the mutation didn't affect the intrinsic GTP-binding, nucleotide exchange or GTPase activity of Bsar1p.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.1
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• pp.54-58
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• 2006

To find out the effectiveness of clinical examination for the diagnosis of respiratory tuberculosis, a 78 respiratory tuberculosis patient,s group was matched by sex and age with 78 control healthy subjects. In the result of blood chemistry, mean values of $123.5{\pm}62.04mg/dL$ in glucose, $429.01{\pm}150.77IU/L$ in LDH, and $44.51{\pm}43.76IU/L$ in ${\gamma}$-GTP, were higher than that of the controls (healthy subjects), and $3.51{\pm}0.68mg/dL$ in albumin was lower than that of the controls. In the result of the haematology examination, mean values of $12.52{\pm}3.27g/dL$ in hemoglobin, $36.72{\pm}7.28%$ in hematocrit, and $24.61{\pm}12.36%$ in lymphocyte, were lower than that of the controls, $9.23{\pm}5.25%$ in monocyte $78.30{\pm}37.35mm/hr$ in ESR, and $48.45{\pm}35.15U/L$ in ADA were higher than that of the controls. For the comparisons of the tuberculosis patients values from normal reference values, 22.2% in glucose, 22.4% in LDH, 25.0% in ${\gamma}$-GTP, 35.4% in albumin, 88% in ESR, and 88.6% in ADA, showed abnormal values. We concluded that the values of glucose, ${\gamma}$-GTP, albumin, WBC, RBC, hemoglobin, hematocrit, lymphocyte, monocyte, ADA, and the ESR were useful in tuberculosis diagnosis.

• The Korean Journal of Pharmacology
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• v.32 no.2
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• pp.151-158
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• 1996

Following the subcutaneous administration of $R(-)N^6-(2-phenylisopropyl)adenosine(600\;nmol/kg/hr)$ to rats for 1 week using t$Alzet^{\circledR}$ mini-osmotic pumps, $A_1$ adenosine receptor functions were determined using $[^3H]DPCPX$ binding, $[^{35}S]GTP_{\gamma}S$ binding, and adenylyl cyclase assays. $A_1$ adenosine receptor binding and the inhibition of adenylyl cyclase activity by PIA was not altered in cerebrocortical membranes prepared from PIA-treated rats. However, there was a significant decrease in the $A_1$ adenosine receptor-mediated stimulation of $[^{35}S]GTP_{\gamma}S$ binding to cerebrocortical membranes prepared from PIA-treated rats(22.0% decrease in basal activity; 19.7% decrease in maximal activity). These results suggest that the desensitization of $A_1$ adenosine receptors following chronic administration involves agonist-induced uncoupling of the receptors from G proteins rather than alteration of $A_1$ adenosine receptor molecules. It is also suggested that the determination of stimulation of $[^{35}S]GTP_{\gamma}S$ binding to G proteins is a suitable tool in studying the receptor regulation including desensitization

• Korean Journal of Microbiology
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• v.38 no.3
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• pp.173-179
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• 2002

The functions of riboflavin synthesis genes ( ribI,II,III and IV) found immediately downstream of luxG in the lux operon from Photobacterium species were identified using the biochemical and genetical analysis. The ribI-III gene codes for protein corresponding to that coded by the second (riboflavin synthase), third (3,4-dihydroxy 2-butanone 4-phosphate synthase/GTP cyclohydrolase II) and fourth (lumazine synthase) gene, respectively, of Bacillus subtilis rib operon with the respective gene procuct sharing 41-50% amino acid sequence identity. Unexpectedly, the sequence of the ribIV product of Photobacterium phosphoreum does not correspond in sequence to the protein encoded by the fifth rib gene of Bacillus subtilis. Instead the gene (ribIV) codes for a polypeptide similar in sequence to GTP cyclohydrolase II of Escherichia coli and the carboxy terminal domain of the third rib gene from Bacillus subtilis. Complementation of Escherichia coli riboflavin auxotrophs showed that the function of the gene products of ribII and ribIV are DHBP synthase and GTP cyclohydrolase II, respectively. In addition the experiment, showing that increase in thermal stability of riboflavin synthase coded by ribIon coexpression with ribIII, provided indirect evidence that the latter gene codes for lumazine synthase.

• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1567-1577
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• 2020

Urban land cover classification is role in urban planning and management. So, it's important to improve classification accuracy on urban location. In this paper, machine learning model, Support Vector Machine (SVM) and Artificial Neural Network (ANN) are proposed for urban land cover classification based on high resolution satellite imagery (KOMPSAT-3A). Satellite image was trained based on 25 m rectangle grid to create training data, and training models used for classifying test area. During the validation process, we presented confusion matrix for each result with 250 Ground Truth Points (GTP). Of the four SVM kernels and the two activation functions ANN, the SVM Polynomial kernel model had the highest accuracy of 86%. In the process of comparing the SVM and ANN using GTP, the SVM model was more effective than the ANN model for KOMPSAT-3A classification. Among the four classes (building, road, vegetation, and bare-soil), building class showed the lowest classification accuracy due to the shadow caused by the high rise building.

• Molecules and Cells
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• v.27 no.5
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• pp.583-589
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• 2009

GTP cyclohydrolase I (GTPCH) is a key enzyme in the de novo synthesis of tetrahydrobiopterin. Previously, the Drosophila melanogaster GTPCH gene has been shown to be expressed from two different promoters (P1 and P2). In our study, the 5'-flanking DNA regions required for P1 and P2 promoter activities were characterized using transient expression assay. The DNA regions between -98 and +31, and between -73 and +35 are required for efficient P1 and P2 promoter activities, respectively. The regions between -98 and -56 and between -73 and -41 may contain critical elements required for the expression of GTPCH in Drosophila. By aligning the nucleotide sequences in the P1 and P2 promoter regions of the Drosophila melanogaster and Drosophila virilrs GTPCH genes, several conserved elements including palindromic sequences in the regions critical for P1 and P2 promoter activities were identified. Western blot analysis of transgenic flies transformed using P1 or P2 promoter-lacZ fusion plasmids further revealed that P1 promoter expression is restricted to the late pupae and adult developmental stages but that the P2 promoter driven expression of GTPCH is constitutive throughout fly development. In addition, X-gal staining of the embryos and imaginal discs of transgenic flies suggests that the P2 promoter is active from stage 13 of embryo and is generally active in most regions of the imaginal discs at the larval stages.

• Journal of Nutrition and Health
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• v.31 no.8
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• pp.1217-1225
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• 1998

This study was conducted to investigate the effects of shellfish on lipid metabolism in rats fed high fat supplements. Male sprague-dawley rats weighting approximately 165g were fed a basal diet, a high fat diet, or a high fat diet plus shellfish for 4 weeks. The shellfishes on the were oyster, hard-shelled mussel, little neck clam, and march clam. Alfter 4 weeks high fat diet, supplementation of 20% lard significantly increased plasma. GOT, GPT, ${\gamma}$-GTP , and liver triglyceride (TG). Plasma GOT, GPT, ${\gamma}$-GTP , triglyceride, and total cholestrerol levels were significantly lower in shellfish groups than in basal and high-fat groups regardless of high-fat supplementation (p<0.05). The total lipid and cholesterol content in liver showed similar results(p<0.05). There were no differences in glucose, HDL-cholesterol in plasma and total cholesterol and total lipid in liver between basal and high-fat supplemented diets. Liong chain fatty acids, specific components of shellfishes group, were exclusively higher than in basal and high-fat diets, and were most well-reflected in liver and plasma. From the above results, the hypolipidemic effects of shellfish were detected in the process of inducing hyperlipidemia by high-fat supplement.

• The Journal of Internal Korean Medicine
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• v.21 no.1
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• pp.108-115
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• 2000

Objective : To investigate the hepatoprotective effects of Gami-oryungsan on the liver damage induced by bromobenzene. Method : The development of fibrosis and acute liver injury was examined by the chemical analysis of AST, AL T, ${\gamma}$-GTP . and epoxide hydrolase glutathione S-transferase glutathione peroxidase enzyme activity, lipidoperoxide levels, glutathione levels were measured and oberved. Results : The increasing levels of lipidoperoxide was decreased proportionally according to dose of extract GO. Epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity highly increased in GO pre-acupunctured group compared with the group treated with only bromobenzene. The increase of serum AST, AL T, ${\gamma}$-GTP enzyme activity of mice by bromobenzene was inhibited by the administration of GO. Lipidoperoxide levels in rat's liver decreased compared to the case of bromobenzene-treated group. The levels of Glutathione decreased by bromo benzene were increased highly in GO pre-acupunctured group. Conclusion : These results suggest that GO extract recovers the damage of liver due to bromobenzene intoxication by decreasing the lipid peroxidation AST AL T ${\gamma}$-GTP enzyme activity and increasing epoxide hydrolase glutathioneS-transferase glutathione peroxidase enzyme activity, glutathione levels.

• BMB Reports
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• v.41 no.7
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• pp.555-560
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• 2008

The interaction of the rod GTP binding protein, Transducin ($G_t$), with bleached Rhodopsin ($R^*$) was investigated by measuring radiolabeled guanine nucleotide binding to and release from soluble and/or membrane-bound Gt by reconstituting $G_t$ containing bound GDP ($G_t$-GDP) or the hydrolysis-resistant GTP analog guanylyl imidodiphosphate ($G_t$-p[NH]ppG) with $R^*$ under physiological conditions. Release of GDP and p[NH]ppG from $G_t$ occurred to the same extent and with the same light sensitivity both in the presence and absence of added GTP. Significant amounts of $G_t$ without bound nucleotide ($G_{t^-}$) were generated. When ROS containing bleached rhodopsin ($R^*$) were centrifuged in low ionic strength buffer, $G_{t^-}$ remained associated with the membrane fraction, whereas $G_t$-GDP remained in the soluble fraction. These results suggest that $G_t$-GDP and $G_t$-p[NH]ppG have similar affinities for $R^*$. The results also suggest that $G_{t^-}$, rather than $G_t$-GDP, is the moiety which exhibits tight, "light-induced" binding to rhodopsin.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.274-277
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• 2012

Cytokinesis is the final stage of cell division, dividing one mother cell into two daughter cells. For the cutting of a plasma membrane during bacterial cytokinesis, a tubulin homolog FtsZ protein is recruited from the cytoplasm to the division site. FtsZ protein polymerizes in a GTP-dependent manner and its N-terminal domain has a GTPase activity. In this study, we have begun to characterize FtsZ from Staphylococcus aureus (SA). Full-length SA FtsZ was cloned into pRSFDuet-1 vector and the clone was transformed into a BL21 (DE3) star cell. The recombinant SA FtsZ protein was purified using Ni-NTA affinity chromatography and dialysis. Using a spectrofluorometer, we showed that SA FtsZ undergoes a GTP-dependant polymerization in vitro. The polymer of the SA FtsZ protein disappeared after a few minutes, suggesting that the polymer is degraded as the GTP is consumed. This assay system may well be applied for inhibitor screening targeting S. aureus FtsZ.