• Molecules and Cells
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• v.19 no.1
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• pp.149-154
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• 2005

Cyclic nucleotide-gated (CNG) channels encoded by the tax-4 and tax-2 genes are required for chemosensing and thermosensing in the nematode C. elegans. We identified a gene in the C. elegans genome, which we designated cng-1, that is highly homologous to tax-4. Partial CNG-1 protein tagged with green fluorescent protein was expressed in several sensory neurons of the amphid. We created a deletion mutant of cng-1, cng-1 (jh111), to investigate its in vivo function. The mutant worms had no detectable abnormalities in terms of their basic behavior or morphology. Whereas tax-4 and tax-2 mutants failed to respond to water-soluble or volatile chemical attractants, the cng-1 null mutant exhibited normal chemotaxis to such chemicals and a tax-4;cng-1 double mutant had a similar phenotype to tax-4 single mutants. Interestingly, cng-1 and tax-4 had a synergistic effect on brood size.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.527-535
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• 2021

Sclerostin (SOST), a regulator of bone formation in osteocytes, inhibits the canonical Wnt signaling by interacting with low-density lipoprotein receptor-related protein 5/6 (LRP5/6) to prevent Wnt binding. Loss-of-function mutations of the SOST gene caused massive bone outgrowth and SOST-null mouse exhibited a high bone density phenotype. Therefore, SOST has been suggested as a promising therapeutic target for osteoporosis. A few previous studies with X-ray crystallography identified the binding interfaces between LRP6 and SOST, but there are limitations in these studies as they used truncated SOST protein or SOST peptide. Here, we analyzed the conformational dynamics of SOST-LRP6 E1E2 complex using hydrogen/deuterium exchange mass spectrometry (HDX-MS). We examined the effect of the C-terminal tail of SOST on LRP6 conformation upon complex formation. HDX-MS analysis suggested a new potential binding interface for the C-terminal region of SOST that was missing from the previous crystal structure of the SOST-LRP6 E1E2 complex.

• The Journal of Internal Korean Medicine
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• v.28 no.3
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• pp.453-463
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• 2007

Backgrounds : Glutathione-s-transferase (GST) is a kind of phase II metabolism enzyme and plays an important role in the detoxification of various toxic chemicals. It was reported that the genetic polymorphism of GSTM1 and GSTT1 genes may be responsible for asthma development and susceptibility to allergy. Traditional oriental medicine uses a unique diagnostic technique. differentiation-syndrome. to analyze signs and symptoms of patients synthetically. Through differentiation-syndrome. asthma patients can be divided into two groups: the deficiency syndrome group (DSG) and the excess syndrome group (ESG). Objectives : The purpose of this study was to investigate the possible association of GST gene polymorphism with clinical phenotype by differentiation-syndrome of bronchial asthma patients. Materials and Methods : One hundred and ten participants were evaluated by pulmonary function test. Patients with 53 DSG and 31 ESG by differentiation-syndrome were assessed for genetic analysis. GSTM1 and GSTT1 deletion polymorphism was performed by polymerase chain reaction (PCR). Results : GSTM1 gene deletion was detected in 43.4% of individuals in the DSG and in 38.71 % in the ESG. The distribution of GSTM1 polymorphism between DSG and ESG was not significantly different [$x^2$=0.1767, p=0.6742; OR(95% CI)=1.2139(0.4915-2.9979)]. The proportion of GSTT1 null genotypes was 41.51% in the DGS and 45.16% in the ESG. The distribution of GSTT1 polymorphism between DSG and ESG was also not significantly different [$x^2$=0.1065, p=0.7442; OR(95% CI)=0.8618(0.3525-2.1065)]. In the combined analysis of GSTM1 and GSTT1 genes, the frequency of both null type of GSTM1/GSTT1 genes was not significantly different from both positive type of GSTM1/GSTT1 genes[$x^2$=0.0768, p=0.7817; OR(95% CI)=1.2000(0.3303-4.3602)] Conclusions : These results indicate that polymorphism of the GST gene might not be associated with the symptomatic classification of DSG and ESG by differentiation-syndrome in Korean asthmatics.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.4
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• pp.234-241
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• 2000

The Saccharomyces cerevisiae PMR1 gene encodes a Ca2+-ATPase localized in the Golgi. We have investigated the effects of PMR1 disruption in S. cerevisiae on the glycosylation and secretion of three heterologous glycoproteins, human ${\alpha}$1-antitrypsin (${\alpha}$1-AT), human antithrombin III (ATHIII), and Aspergillus niger glucose oxidase (GOD). The pmr1 null mutant strain secreted larger amounts of ATHIII and GOD proteins per a unit cell mass than the wild type strain. Despite a lower growth rate of the pmr1 mutant, two-fold higher level of human ATHIII was detected in the culture supernatant from the pmr1 mutant compared to that of the wild-type strain. The pmr1 mutant strain secreted ${\alpha}$1-AT and the GOD proteins mostly as core-glycosylated forms, in contrast to the hyperglycosylated proteins secreted in the wild-type strain. Furthermore, the core-glycosylated forms secreted in the pmr1 mutant migrated slightly faster on SDS-PAGE than those secreted in the mnn9 deletion mutant and the wild type strains. Analysis of the recombinant GOD with anti-${\alpha}$1,3-mannose antibody revealed that GOD secreted in the pmr1 mutant did not have terminal ${\alpha}$1,3-linked mannose unlike those secreted in the mnn9 mutant and the wild type strains. The present results indicate that the pmr1 mutant, with the super-secretion phenotype, is useful as a host system to produce recombinant glycoproteins lacking high-mannose outer chains.

• Korean Journal of Microbiology
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• v.30 no.1
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• pp.37-41
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• 1992

The KEM1 gene is known to affect microtubule and spindle pole body function during the cell division cycle in Saccharomjyces cerevisiae. To identify new genes with functions similar or related to those of KEM1, we isolated a high copy suppressor gene (ROK1) that suppresses the kem1 mutation when cloned on a high copy number plasmid but not on a low copy number plasmid. Two clones which suppress both the benomyl hypersensitivity and the $Kar^{-}$ enhancing phenotype of kem1 null mutation were isolated and were shown to have a 9.0 kb identical insert by restriction endonuclease analysis. The restriction map constructed indicates that this suppressor gene, ROK1 is not KEM1. Subcloning experiments suggest that the functional region of ROK1 is at least 3.0kb in size.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.11-11
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• 2018

Cryphonectria parasitica, chestnut blight fungus, has a characteristic of decreasing pathogenicity when infected with Cryphonectria hypovirus 1. C. parasitica is known to be one of the most representative model systems used to observe the interaction between viruses, plants and fungi. The mitogen-activated protein kinase (MAPK) pathway, which is well conserved in various organisms ranging from yeast to humans, functions in relaying phosphorylation-dependent signals within MAPK cascades to diverse cellular functions involved in the regulation of pheromone, cell wall integrity, and osmotolerance in filamentous fungi. Several genes in the MAPK pathway were revealed to be regulated by hypovirus, or to be involved in pathogenicity in C. parasitica. Among these pathways, the CWI pathway has aroused interest because CpBck1, an ortholog of yeast Bck1 (a CWI MAPKKK), was previously reported to be involved in cell wall integrity and sectorization. Interestingly, sporadic sectorization was observed in the CpBck1 mutant and sectored phenotypes were stably inherited in the progeny that were successively transferred from sectored mycelia. In this study, we analyzed the biological function of CpSlt2, downstream gene of CpBck1, to confirm whether the sectorization phenomenon occurred in the specific single gene or cell wall integrity (CWI) pathway. As results, the CpSlt2-null mutant exhibited marked changes in colonial growth, near absence of conidiation and aerial hyphae, abnormal pigmentation, CWI-related phenotypic defects, and dramatically impaired virulence. As cultivation of the mutant strains progressed, the majority of the colonies showed sporadic sectorization and mycelia from the sectored area stably maintained the sectored phenotype. These results suggest that the unique sectorization is CWI pathway-specific, though the components in the same CWI pathway have common and specific functions.

• Journal of dental hygiene science
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• v.9 no.4
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• pp.427-433
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• 2009

Nuclear factor I-C (NFI-C) null mice demonstrated aberrant odontoblast differentiation and abnormal dentin formation. In order to elucidate the mechanisms responsible for these changes, we evaluated the expression of dentin matrix gene after over-expression and inactivation of NFI-C in MDPC-23 cells by reverse transcription-polymerase chain reaction (RT-PCR) analysis. Collagen type I (Col I), osteocalcin (OC), and dentin sialophosphoprotein (DSPP) expression was decreased after inactivation of NFI-C. However, bone sialoprotein (BSP) expression was dramatically increased after inactivation of NFI-C. ALP and DMP4 expression was not changed after inactivation of NFI-C. The expression of alkaline phoshatase (ALP) and dentin matrix protein 4 (DMP4) was increased after over-expression of NFI-C, while Col I, OC, DSPP, and BSP expression was decreased. These findings suggest that odontoblasts after loss of NFI-C lost the phenotype of odontoblasts and acquired those of osteoblasts.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.476-486
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• 2008

Background: TRAIL (TNF-related apoptosis inducing ligand) is a newly identified member of the TNF gene family which appears to have tumor-selective cytotoxicity due to the distinct decoy receptor system. TRAIL has direct access to caspase machinery and induces apoptosis regardless of p53 phenotype. Therefore, TRAIL has a therapeutic potential in lung cancer which frequently harbors p53 mutation in more than 50% of cases. However, it was shown that TRAIL also could activates $NF-{\kappa}B$ in some cell lines which might inhibit TRAIL-induced apoptosis. This study was designed to investigate whether TRAIL can activate $NF-{\kappa}B$ in lung cancer cell lines relatively resistant to TRAIL-induced apoptosis and inhibition of $NF-{\kappa}B$ activation using proteasome inhibitor MG132 which blocks $I{\kappa}B{\alpha}$ degradation can sensitize lung cancer cells to TRAIL-induced apoptosis. Methods: A549 (wt p53) and NCI-H1299 (null p53) lung cancer cells were used and cell viability test was done by MTT assay. Apoptosis was confirmed with Annexin V assay followed by FACS analysis. To study $NF-{\kappa}B$-dependent transcriptional activation, a luciferase reporter gene assay was used after making A549 and NCI-H1299 cells stably transfected with IgG ${\kappa}-NF-{\kappa}B$ luciferase construct. To investigate DNA binding of $NF-{\kappa}B$ activated by TRAIL, electromobility shift assay was used and supershift assay was done using anti-p65 antibody. Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation. Results: A549 and NCI-H1299 cells were relatively resistant to TRAIL-induced apoptosis showing only 20~30% cell death even at the concentration 100 ng/ml, but MG132 ($3{\mu}M$) pre-treatment 1 hour prior to TRAIL addition greatly increased cell death more than 80%. Luciferase assay showed TRAIL-induced $NF-{\kappa}B$ transcriptional activity in both cell lines. Electromobility shift assay demonstrated DNA binding complex of $NF-{\kappa}B$ activated by TRAIL and supershift with p65 antibody. $I{\kappa}B{\alpha}$ degradation was proven by western blot. MG132 completely blocked both TRAIL-induced $NF-{\kappa}B$ dependent luciferase activity and DNA binding of $NF-{\kappa}B$. Conclusion: This results suggest that inhibition of $NF-{\kappa}B$ can be a potentially useful strategy to enhance TRAIL-induced tumor cell killing in lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2765-2769
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• 2013

Background: A close association between patterns identified by magnifying narrow-band imaging (M-NBI) and histological type has been described. M-NBI patterns were also recently reported to be related to the mucin phenotype; however, detials remain unclear. Materials and Methods: We investigated the cellular differentiation of gastric cancer lesions, along with their mucosal distribution observed by M-NBI. Ninety-seven depressed-type early gastric cancer lesions (74 differentiated and 23 undifferentiated adenocarcinomas) were visualized by M-NBI. Findings were divided into 4 patterns based on abnormal microvascular architecture: a chain loop pattern (CLP), a fine network pattern (FNP), a corkscrew pattern (CSP), and an unclassified pattern. Mucin phenotypes were judged as gastric (G-type), intestinal (I-type), mixed gastric and intestinal (M-type), and null (N-type) based on 4 markers (MAC5AC, MUC6, MUC2, and CD10). The relationship of each pattern of microvascular architecture with organoid differentiation indicated by cancer cell differentiation and its distribution in each histological type of early gastric cancer was investigated. Results: All CLP and FNP lesions were differentiated. The cancer cell distribution showed organoid differentiation in 84.2% (16/19) and 61.1% (22/36) of the two types of lesions, respectively, and there was a significant difference from the unclassified pattern with organoid differentiation (p<0.001). Almost all (94.7%; 18/19) CSP lesions were undifferentiated, and organoid differentiation was observed in 72.2% (13/18). There was a significant difference from the unclassified pattern with organoid differentiation (p<0.05). Conclusions: Cellular differentiation and distribution are associated with microvascular architecture observed by M-NBI.

• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.638-645
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• 2004

Background : Uteroglobin is a protein produced by the normal bronchial epithelium and its expression level is lower in non-small cell lung cancer tissues and cell lines. It mainly functions as an anti-inflammatory, and when it is overexpressed in cancer cells, the neoplastic phenotype is antagonized. cPLA2 and COX-2, which are also associated with inflammation, were reported to be related to cancer. The relationship between cPLA2, COX-2 and uteroglobin is unclear. The relationship between uteroglobin and ERK, which is related to cell growth, is also not unclear. This study investigated the changes in the cPLA2 and COX-2 expression levels and the ERK activities after the overexpression of uteroglobin in non-small cell lung cancer cell lines. Methods : The A549 and NCI-H460 cell lines were infected by adenovirus-null and adenovirusuteroglobin. The cChange in the cPLA2, COX-2 expression level and ERK activity after uteroglobin overexpression was measured by Western blot. The change in MMP activity was measured by zymography. Results : Western blot revealed decreased expression levels of cPLA2, and COX-2, and increased pERK levels in nonsmall cell lung cancer cells after uteroglobin overexpression. Zymography revealed no changes in the MMP-2 activity and lower MMP-9 activity. U0126, which is a specific inhibitor of ERK-activating kinase MEK-1/-2, prevented the decrease in the MMP-9 activity Conclusions : A decrease in cPLA2 expression, COX-2 expression, MMP-9 activity and a increase in ERK activity may be related to the anticancer effects of uteroglobin in nonsmall cell lung cancer cells.