• Polymer(Korea)
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• v.25 no.5
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• pp.736-743
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• 2001

An electro- active polymer (EAP) (poly(2-acrylamido-2- methyl propane sulfonic acid), PAMPS) gel crosslinked with N,N-methylenebisacrylamide (MBAA) has been prepared by free radical polymerization in aqueous solution with potassium persulfate as initiator PAMPS gel was swollen in surfactant solution to substitute surfactant for using as actuator. PAMPS gel showed a large movement in the surfactant solution by electric field. PAMPS gel showed the reversible binding and fast response rate. Bending mechanism of gel is related to the cooperative process of hydrophobic interaction, swelling-deswelling of gel and the electrostatic attraction between anode (+) and the anions of PAMPS gel. The response rate of PAMPS gel was increased as the applied potential and the degree of cross-linkage were increased. The response rate was increased as the bending cycle was repeated, but it was decreased with increasing the gel thickness.

• BMB Reports
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• v.41 no.1
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• pp.29-34
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• 2008

The aim of this study was to determine whether single nucleotide polymorphisms (SNP) in the beef cattle adipocyte fatty-acid binding protein 3 and 4 (FABP3 and FABP4) genes are associated with carcass weight (CW) and back fat thickness (BF) of beef cattle. By direct DNA sequencing in 24 unrelated Korean native cattle, we identified 20 SNPs in FABP3 and FABP4. Among them, 10 polymorphic sites were selected for genotyping in our beef cattle. We performed SNP, haplotype and linkage disequilibrium studies on 419 Korean native cattle with the 10 SNPs in the FABP genes. Statistical analysis revealed that 220A>G (I74V) and 348+303T>C polymorphisms in FABP4 showed putative associations with BF traits (P=0.02 and 0.01, respectively). Our findings suggest that the polymorphisms in FABP4 may play a role in determining one of the important genetic factors that influence BF in beef cattle.

• BMB Reports
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• v.31 no.1
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• pp.64-69
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• 1998

Recent studies have suggested that integrin (CR3) participates in the signal transduction pathways of certain GPI-anchored phagocytic receptors including $Fc{\gamma}RIIIB$. One consequence of this functional linkage is an inducible association between CR3 and cortical microfilaments that is triggered by $Fc{\gamma}RIIIB$ binding to immobilized immune complexes (IC). That this signaling event requires the co-expression of $Fc{\gamma}RIIIB$ with CR3 was documented by the use of NIH 3T3 transfectants expressing both CR3 and $Fc{\gamma}RIIIB$ (clone 3-23), CR3 alone (clone 3-19), and $Fc{\gamma}RIIIB$ alone (clone 3-15). Pretreatment of 3-23 cells with protein kinase inhibitors such as staurosporine and methyl 2,5-dihydroxycinnamate (MDHC) blocked IC-stimulated CR3 microfilament proximity without affecting the extent to which $Fc{\gamma}RIIIB$ constrains the lateral membrane mobility of a subset of CR3 on the cell surface (as measured in fluorescence recovery after photobleaching experiments). These data support that CR3 and $Fc{\gamma}RIIIB$ molecules are physically and functionally associated and that ligation of FcgRIIIB triggers CR3-dependent signal transduction.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.591-599
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• 2020

Phytophthora root and stem rot reduce soybean yields worldwide. The use of R-gene type resistance is currently crucial for protecting soybean production. The present study aimed to identify the genomic location of a gene conferring resistance to Phytophthora sojae isolate 2457 in the recombinant inbred line population developed by a cross of Daepung × Daewon. Singlemarker analysis identified 20 single nucleotide polymorphisms associated with resistance to the P. sojae isolate 2457, which explained ~67% of phenotypic variance. Daewon contributed a resistance allele for the locus. This region is a well-known location for Rps1 and Rps7. The present study is the first, however, to identify an Rps gene locus from a major soybean variety cultivated in South Korea. Linkage analysis also identified a 573 kb region on chromosome 3 with high significance (logarithm of odds = 13.7). This genomic region was not further narrowed down due to lack of recombinants within the interval. Based on the latest soybean genome, ten leucine-rich repeat coding genes and four serine/ threonine protein kinase-coding genes are annotated in this region, which all are well-known types of genes for conferring disease resistance in crops. These genes would be candidates for molecular characterization of the resistance in further studies. The identified R-gene locus would be useful in developing P. sojae resistant varieties in the future. The results of the present study provide foundational knowledge for researchers who are interested in soybean-P. sojae interaction.

• Journal of the Korean Applied Science and Technology
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• v.18 no.2
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• pp.111-117
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• 2001

Density, viscosity, conductance, dye solubility and carbon-13 nmr studies were performed in aqueous solution of three disodium 4-n-alkyl-3-sulfonatosuccinate anionic surfactant at $20^{\circ}C$. The cmc values were 0.14 mol/l for the disodium-4-n-octyl-3-sulfonatosuccinate($R_{8)S$), 0.041mol/l for the disodium-4-n-decyl-3-sulfonatosuccinate($R_{10}S$), and 0.018mol/l for the disodium-n-dodecyl-3-sulfonatosuccinate <$R_{12}S$). The aggregation numbers determined viscometrically and conductimetrically were 28 for $R_{8}S$, 48 for $R_{10}S$, and 67 for $R_{12}S$. The volume changes upon micellization were $8.9cm^{3}/mol$ for $R_{8}S$, $9.5cm^{3}/mol$ for $R_{10}S$, and $10.1cm^{3}/mol$ for $R_{12}S$. Binding constants for the dye pada to the micelles and the fractions of unbound counter-ion were also obtained. The two polar heads with their carbon linkage were likely in an aqueous environment in the $R_{8}S$ micelles with the micelles themselves being spherical.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.4
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• pp.287-297
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• 2001

Contraction of smooth muscle is initiated by an increase in cytosolic $Ca^{2+}$ leading to activation of $Ca^{2+}$/ calmodulin-dependnet myosin light chain (MLC) kinase and phosphorylation of MLC. The types of contraction and signaling mechanisms mediating contraction differ depending on the region. The involvement of these different mechanisms varies depending on the source of $Ca^{2+}$ and the kinetic of $Ca^{2+}$ mobilization. $Ca^{2+}$ mobilizing agonists stimulate different phospholipases $(PLC-{\beta},\;PLD\;and\;PLA_2)$ to generate one or more $Ca^{2+}$ mobilizing messengers $(IP_3\;and\;AA),$ and diacylglycerol (DAG), an activator of protein kinase C (PKC). The relative contributions of $PLC-{\beta},\;PLA_2$ and PLD to generate second messengers vary greatly between cells and types of contraction. In smooth muscle cell derived form the circular muscle layer of the intestine, preferential hydrolysis of $PIP_2$ and generation of $IP_3$ and $IP_3-dependent\;Ca^{2+}$ release initiate the contraction. In smooth muscle cells derived from longitudinal muscle layer of the intestine, preferential hydrolysis of PC by PLA2, generation of AA and AA-mediated $Ca^{2+}$ influx, cADP ribose formation and $Ca^{2+}-induced\;Ca^{2+}$ release initiate the contraction. Sustained contraction, however, in both cell types is mediated by $Ca^{2+}-independent$ mechanism involving activation of $PKC-{\varepsilon}$ by DAG derived form PLD. A functional linkage between $G_{13},$ RhoA, ROCK, $PKC-{\varepsilon},$ CPI-17 and MLC phosphorylation in sustained contraction has been implicated. Contraction of normal esophageal circular muscle (ESO) in response to acetylcholine (ACh) is linked to $M_2$ muscarinic receptors activating at least three intracellular phospholipases, i.e. phosphatidylcholine-specific phospholipase C (PC-PLC), phospholipase D (PLD) and the high molecular weight (85 kDa) cytosolic phospholipase $A_2\;(cPLA_2)$ to induce phosphatidylcholine (PC) metabolism, production of diacylglycerol (DAG) and arachidonic acid (AA), resulting in activation of a protein kinase C (PKC)-dependent pathway. In contrast, lower esophageal sphincter (LES) contraction induced by maximally effective doses of ACh is mediated by muscarinic $M_3$ receptors, linked to pertussis toxin-insensitive GTP-binding proteins of the $G_{q/11}$ type. They activate phospholipase C, which hydrolyzes phosphatidylinositol bisphosphate $(PIP_2),$ producing inositol 1, 4, 5-trisphosphate $(IP_3)$ and DAG. $IP_3$ causes release of intracellular $Ca^{2+}$ and formation of a $Ca^{2+}$-calmodulin complex, resulting in activation of myosin light chain kinase and contraction through a calmodulin-dependent pathway.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.406-414
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• 2005

The genetic instability of cancer cells may be related to inappropriately activated DNA repair pathways. In present study, the modulated expression of DNA-dependent protein kinase (DNA-PK), a major DNA repair protein, in human cancer metastatic cells was tested. The expressions of Ku70/80, regulatory subunit of DNA-PK, and the Ku DNA-binding activity in various highly metastatic cell lines were higher than those in each parental cell line. Also, the expression of DNA-PKcs, catalytic subunit of DNA-PK, and the kinase activity of the whole DNA-PK complex in highly metastatic cells were significantly increased as compared to those of parental cells, suggesting that the enhanced DNA repair capacity of metastatic cells could be associated with aberrant use of DNA repair, which may mediate tumor progression and metastatic potential. Increased EGFR (epidermal growth factor receptor) signaling has been associated with tumor invasion and metastasis, and the linkage between EGFR-mediated signaling and DNA-PK has been suggested. This study showed that PKI166, the new EGFR tyrosine kinase inhibitor, modulated the expressions of Ku70/80 and DNA-PKcs and also revealed the chemosensitization effect of PKI166 against metastatic cells may be in part due to inhibition of Ku70/80. These results suggest that interference in EGFR signaling by EGFR inhibitor resulted in the impairment of DNA repair activity, and thus DNA-PK could be possible molecular targets for therapy against metastatic cancer cells.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.3
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• pp.31-37
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• 2010

Chitinases (EC 3.2.1.14) hydrolyze the ${\beta}$-1,4-linkages in chitin, the second most abundant polymer of N-acetyl-${\beta}$-D-glucosamine which is a structural component of protective biological matrices such as fungal cell walls and insect exoskeletons. The glycosyl hydrolases 18 family including chitinases is an ancient gene family widely expressed in archea, prokaryotes and eukaryotes. Since earthworms live in the soil with a lot of microbial activities and fungi are supposed to be a major component of the diet of earthworm, it has been reported that there would be appropriate immune system to protect themselves from microorganisms attacks. In this study, the novel chitinase, EaChi, from the midgut of earthworm, Eisenia andrei, were identified and characterized. To obtain full-length cDNA sequence of chitinase, RT-PCR and RACE-PCR analyses were carried out by using the previously identified EST sequence amongst cDNA library established from the midgut of E. andrei. EaChi, a partial chitinase gene, was composed of 927 nucleotides encoding 309 amino acids. By the multiple sequence alignments of amino acids with other different species, it was revealed that EaCHI is a member of glycosyl hydrolases 18 family, which has two highly conserved domains, substrate binding and catalytic domain.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.111-123
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• 2011

This study aims to present the basic materials, which lead us to preserve the Korea Rice Terrace as scenic sites resources and study it continuously, through researching about the present status and the preservation method of the Rice Terrace in Korea, China and Japan. The results of this study are as follows. First, The Rice Terrace has a traditional agricultural technique which minimizing the damage of the scenic view while cultivating the slope. And also, it has the value of one of the Korea unique traditional scenic views. However, The no cultivation land or disappearing desert land of rice terrace were increasing by the disadvantage of operation in land cultivation. Therefore, The Government must need preparing the base of scene resources excavation by executed the established of Korea Rice Terrace Database for preserving of Korea traditional scene. however it is getting to disappearance. And also, The High valued of Rice Terrace by cultural and scenic view which is must managed by designation of scenic sites or monument. Second, The internal and external reference book researched and analyzed results are as followings for understanding about Korea Rice Terrace feature. First of all, The Rice Terrace's dictionary meaning is just difference by each nations. However, Generally speaking that It means the terraced land by cultivated of sloped land. The Rice Terrace has cross relation with mountain valley and piedmont slope cultivation in location of condition. It occurred era is before approximately estimated from 3000 of years until 6000 of years. It can divide two type by topography shape those are slope and valley type. However, The natural element of forest has very big position in this part. But, The Rice Terrace is just managed and designated by the scenic sites with the Cultural Properties Protection Law. It must needs more binding force and effectiveness for the Rice Terrace scenic view plan establishment by scenic laws and farming and fishing village laws etc. I think that it must need the Rice Terrace related law establishment as soon as possible for efficient preservation and management of the Rice Terrace. Third, The Rice Terrace were researched and analyzed results are as followings those were executed at the Korea, China and Japan. The Korea and Japan have good Rice Terrace Characteristic. And also, The high valued scenic sites area were good managed by the Cultural Properties Protection Law as well as the superior scenic valued Rice Terrace in China. Those are also managed by designated scenic sites for protection and preservation positively. Those were managed by each autonomous district management Department. The each nation's related laws of Rice Terrace protection were just little bit different. However, The basic purpose is same. for example, it based on superior scenic view preservation and protection. Especially, The Japan's Cultural Properties Law and Scenic law linkage, and China Autonomous district legislation and effectiveness. The Korea Government must need above elements for Korea Rice Terrace culture and scenic view preservation. Fourth, We need inducing the owner system and the policy of Rice Terrace preservation promotion association for efficient preservation of Rice Terrace in japan. The owner system in japan gives the owner of the land a permission to rent the land to Rice Terrace preservation promotion association and the local government. In this system the village would be revitalized by commons in the way of the management of the terraces, beautifying the area around the terraces and etc. And also, Making the each village management operating system for Rice Terrace management through educating civilization. The civilization could receive quick help from a consultative body comprised of experts such as representatives of Cultural Heritage Administration and professors. And it is in a hurry to solve the problem of revitalization of the region by exchange between cities and the village.