• Applied Biological Chemistry
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• v.46 no.1
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• pp.16-22
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• 2003

Interrelation between the antioxidative activities of 70% ethanol extracts from bran fraction of 23 kinds of colored rice and chuchung as a control were examined. Antioxidative activities were evaluated by assaying reducing power, electron-donation ability to DPPH free radical, scavenging activity of hydroxy radical $({\cdot}OH)$ generated through Fenton reaction and inhibitory activity on lipid peroxidation using linoleic acid autoxidation system, respectively. Among 24 varieties of colored rice LK 1-3-6-12-1-1 had the strongest reducing power followed by Elwee, DZ 78, Jumlalocal-1 and SC-45 in decreasing order. The electron-donating ability to DPPH radical was higher in order of HP 883-1-1-1-B-1-1, HP 833-1-3-1-1-1, LK 2-7-12-1-1 and DZ 78. The hydroxy radical scavenging activity was higher in order of DK-1, IR 1544-38-2-2-1-2-2, SC-5 and SC-45 but LK 2-7-12-1-1 had oxidative effect. In the liaoleic acid autoxidation model system, RGS No 336, LK 1B-2-1-1, LK 1B-4-12-1-1, LK 1A-2-12-1-1, LK 2-7-12-1-1 and HP 883-1-1-1-B-1-1 exhibited strong antioxidative activities but Elwee, Jumlalocal-l and SC-45 showed to have oxidative effects. The rice variety of highest pigment content was Elwee and the next were RGS-No 336, IR 1544-38-2-2-1-2-2 and SC-5 with the order of higher content. The reducing power was correlated with the quantity of the pigment in the ethanolic extract of rice bran and SC-5 showed relatively high antioxidative activity in every results of antioxidative activity tests.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.66-83
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• 2002

Recently, we have provided evidence that ginsenosides, the active components of Panax ginseng, utilize pertussis toxin (PTX)-insensitive $G{\alpha}_{q/11}-phospholipase\;C-{\beta}3(PLC-{\beta}3)$ signal transduction pathway for the enhancement of $Ca^{2+}-activated\;Cl^{-}$ current in the Xenopus oocyte (British J. Pharmacol. 132, 641-647, 2001; JBC 276, 48797-48802, 2001). Other investigators have shown that stimulation of receptors linked to $G{\alpha}-PLC$ pathway inhibits the activity of G proteincoupled inwardly rectifying $K^+$ (GIRK) channel. In the present study, we sought to determine whether ginsenosides influenced the activity of GIRK 1 and GIRK 4 (GIRK 1/4) channels expressed in the Xenopus oocyte, and if so, the underlying signal transduction mechanism. In oocyte injected with GIRK 1/4 channel cRNAs, bath-applied ginsenosides inhibited high potassium (HK) solution-elicited GIRK current $(EC_{50}:4.9{\pm}4.3\;{\mu}g/ml).$ Pretreatment of the oocyte with PTX reduced the HK solution-elicited GIRK current by $49\%,$ but it did not alter the inhibitory ginsenoside effect on GIRK current. Prior intraoocyte injection of cRNA(s) coding $G{\alpha}_q,\;G{\alpha}_{11}\;or\;G{\alpha}_q/G{\alpha}_{11},\;but\;not\;G{\alpha}_{i2}\;or\;G{\alpha}_{oA}$ attenuated the inhibitory ginsenoside effect. Injection of cRNAs coding $G{\beta}_{1{\gamma}2}$ also attenuated the ginsenoside effect. Similarly, injection of the cRNAs coding regulators of G protein signaling 1, 2 and 4 (RGS1, RGS2 and RGS4), which interact with $G{\alpha}_i\;and/or\;G{\alpha}_{q/11}$ and stimulates the hydrolysis of GTP to GDP in active GTP-bound $G{\alpha}$ subunit, resulted in a significant reduction of ginsenoside effect on GIRK current. Preincubation of GIRK channel-expressing oocyte in PLC inhibitor (U73122) or protein kinase C (PKC) inhibitor (staurosporine or chelerythrine) blocked the inhibitory ginsenoside effect on GIRK current. On the other hand, intraoocyte injection of BAPTA, a free $Ca^{2+}$ chelator, had no significant effect on the ginsenoside action. Taken together, these results suggest that ginsenosides inhibit the activity of GIRK 1/4 channel expressed in the Xenopus oocyte through a PTX-insensitive and $G{\alpha}_{q/11}$-,PLC-and PKC-mediated signal transduction pathway.

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.471-479
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• 2008

Let $R\;{\in}\;C^{m{\times}m}$ and $S\;{\in}\;C^{n{\times}n}$ be nontrivial unitary involutions, i.e., $R^*\;=\;R\;=\;R^{-1}\;{\neq}\;I_m$ and $S^*\;=\;S\;=\;S^{-1}\;{\neq}\;I_m$. We say that $G\;{\in}\;C^{m{\times}n}$ is a generalized reflexive matrix if RGS = G. The set of all m ${\times}$ n generalized reflexive matrices is denoted by $GRC^{m{\times}n}$. In this paper, an efficient method for the least squares solution $X\;{\in}\;GRC^{m{\times}n}$ of the matrix equation AXB = D with arbitrary coefficient matrices $A\;{\in}\;C^{p{\times}m}$, $B\;{\in}\;C^{n{\times}q}$and the right-hand side $D\;{\in}\;C^{p{\times}q}$ is developed based on the canonical correlation decomposition(CCD) and, an explicit formula for the general solution is presented.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.951-958
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• 2003

Twenty-four cultivars of colored rice seeds were collected inside and outside Korea, and the antioxidant and antimutagenic activity was determined for the solvent-fractionated layers of their bran parts lipid soluble fraction, pigment containing fraction, and pigment component per se. As the serial organic solvent extraction proceeded, the overall tendency of antioxidant activities declined with increased chemical homogeneity of each fraction. This markedly showed the low antioxidativities of the pigment components from LK 1-3-6-12-1-1 and Gillimhukmi. Even all the colored rice cultivars, with considerable antimutagenic activity in 70% ethanolic extract, exhibited mutagenicity when measured with its pigment containing fraction (wx 124-163-45-7-1-1-1 and LKlB-2-1-1 being the strongest). The pigment content in each colored rice seeds decreased in the order of IR 17491-5-4-3-3>LK 1-3-6-12-1-1>LK 1D-2-12-1>RGS No.336, Elwee. In addition, a substantial difference in both chemical composition of the constituents and its amount could be found between the colored rice and cooking rice cultivars. This revealed that, compared to cooking rice, major components of organic solvent fractions from colored rice probably have long hydrocarbon chain moieties.

• BMB Reports
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• v.49 no.8
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• pp.443-448
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• 2016

The arginylation branch of the N-end rule pathway is a ubiquitin-mediated proteolytic system in which post-translational conjugation of Arg by ATE1-encoded Arg-tRNA-protein transferase to N-terminal Asp, Glu, or oxidized Cys residues generates essential degradation signals. Here, we characterized the ATE1^−/− mice and identified the essential role of N-terminal arginylation in neural tube development. ATE1-null mice showed severe intracerebral hemorrhages and cystic space near the neural tubes. Expression of ATE1 was prominent in the developing brain and spinal cord, and this pattern overlapped with the migration path of neural stem cells. The ATE1^−/− brain showed defective G-protein signaling. Finally, we observed reduced mitosis in ATE1^−/− neuroepithelium and a significantly higher nitric oxide concentration in the ATE1^−/− brain. Our results strongly suggest that the crucial role of ATE1 in neural tube development is directly related to proper turn-over of the RGS4 protein, which participate in the oxygen-sensing mechanism in the cells.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.10
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• pp.1496-1502
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• 2006

Skeletal muscle contains slow and fast twitch fibers. These skeletal muscle fibers express type I and type II myosin, respectively, and these myosin isoenzymes have different ATPase activity. The aim of this study was to investigate protein profiles of bovine skeletal muscles by proteomic analysis. Fifty seven spots of distinct proteins were excised and characterized. The expression of sixteen spots was differed in longissimus dorsi muscle with a minimal 2-fold change compared to biceps femoris muscle. The majority of differentially expressed proteins belonged to metabolic regulation-related proteins such as glyceraldehyde 3-phosphate dehydrogenase, triosephosphate isomerase and carbonic anhydrase 3. The real time-PCR assay confirmed an increase or induction of specific genes: RGS12TS isoform, GAPDH, triosephosphate isomerase and carbonic anhydrase. These results suggest that the expression of metabolic proteins is under a specific control system in different bovine skeletal muscle. These observations could have significant implications for understanding the physiological regulation of bovine skeletal muscles.

• Reproductive and Developmental Biology
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• v.35 no.2
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• pp.131-136
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• 2011

The in vitro maturation rate of vitrified-thawed canine oocytes was $30.8{\pm}3.4%$. The in vitro maturation rate of vitrified oocytes was lower than that of the control ($52.0{\pm}2.5%$, p<0.05). The in vitro maturation rate of vitrified-thawed oocytes were significantly (p<0.05) lower than those of fresh oocytes. The in vitro maturation and developmental rates of the vitrified-thawed oocytes were $17.5{\pm}2.5%$ and $8.8{\pm}3.4%$, respectively. This results were lower than the control group ($43.6{\pm}3.2%$ vs $20.0{\pm}3.0%$). SOD1 gene expression of 1~2 mm of follicle size were higher than those of above 6 mm follicle size. SOD2 gene expression of 1~2 mm of follicle size were significantly higher than those of above 6 mm follicle size (p<0.01). The expression pattern of SOD1, 2 was constantly expressed in both groups but strongly expressed in follicles (1~2 mm) group when compared to the above 6 mm follicles. SOD gene expression between groups the fresh and vitrified oocytes groups were significant differences in rates. However, RGS gene expression between groups the fresh and vitrified oocytes groups were no significant differences in rates.

• BMB Reports
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• v.36 no.3
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• pp.326-331
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• 2003

The fission yeast cells that contained the cloned glutathione synthetase (GS) gene showed 1.4-fold higher glutathione (GSB) content and 1.9-fold higher GS activity than the cells without the cloned GS gene. Interestingly, $\gamma$-glutamylcysteine synthetase activity increased 2.1-fold in the S. pombe cells that contained the cloned GS gene. The S. pombe cells that harbored the multi copy-number plasmid pRGS49 (containing the cloned GS gene) showed a higher level of survival on solid media with cadmium chloride (1 mM) or mercuric chloride ($10\;{\mu}M$) than the cells that harbored the YEp357R vector. The 506 bp upstream sequence from the translational initiation point and N-terminal8 amino acid-coding region were fused into the promoteriess $\beta$-galactosidase gene of the shuttle vector YEp367R to generate the fusion plasmid pUGS39. Synthesis of $\beta$-galactosidase from the fusion plasmid pUGS39 was significantly enhanced by cadmium chloride and NO-generating S-nitroso-N-acetylpenicillamine (SNAP) and sodium nitroprusside (SN). It was also induced by L-buthionine-(S,R)-sulfoximine, a specific inhibitor of $\gamma$-glutamylcysteine synthetase (GCS). We also found that the expression of the S. pombe GS gene is regulated by the Atf1-Spc1-Wis1 signal pathway.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.43-43
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• 2003

Large-conductance $Ca^{2+}$-actived $K^{+}$ channels ($BK_{Ca}$ channels) play a key role in setting the pace of contractile activity in muscle and are involved in the regulation of neurotransmitter release in neuron. $BK_{Ca}$ channels are activated by depolarizing membrane potential and the elevated level of intracellular calcium. Using yeast-two hybrid assay, we have identified a novel protein interacting with the cytosolic carboxyl terminus of rSlo, the brain isoform of rat large-conductance $Ca^{2+}$-activated $K^{+}$ channel $\alpha$-subunit. The novel gene encodes 51 kDa protein and is named as SIRK(rSlo-interacting RGS-like protein). SIRK is expressed in various tissues and localized in the cytosolic and the membrane fraction. Biochemical and immunological studies indicated that SIRK physically interacted with the cytosolic region of rSlo. To investigate whether SIRK can modulate the activity of rSlo, GFP-fused SIRK and rSlo were transiently transfected into COS-7 cells and the effects of SIRK was studied using electrophysiological means. We concluded that the overexpression of SIRK alters the surface expression of rSlo channel with only a limited effect on the biophysical characteristics of the channel.the channel.

• Genomics & Informatics
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• v.9 no.2
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• pp.59-63
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• 2011

Obesity provokes many serious human diseases, including various cardiovascular diseases and diabetes. Body mass index (BMI) is a highly heritable trait that is broadly used to diagnose obesity. To identify genetic loci associated with obesity in Asians, we conducted a genome-wide association study (GWAS) of a population of Korean adults (n=6,742, age 40~60 years) and detected six BMI risk loci (TNR, FAM124B, RGS12, NFE2L3, MC4R and FTO) having p< $1{\times}10^{-5}$. However, in the replication study, only melanocortin 4 receptor gene (MC4R) (rs9946888, p=$4.58{\times}10^{-7}$) was replicated with marginal significance (p<0.05) in the second cohort (n=5,102, age 40~60 years). This study indicates that each locus associated with BMI has very weak genetic effect.