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        검색결과 88

        3.
        2019.04 구독 인증기관·개인회원 무료
        The baculovirus expression system is a very useful tool widely used for expression of foreign proteins. To use the baculovirus expression system, a recombinant baculovirus must be prepared. The development of the Bac to Bac system has reduced the time and effort required to produce recombinant baculovirus. But, it will take at least two weeks. Further, it takes more time to measure the activity of recombinant baculovirus. In order to overcome this problem, a virus inducible expression system is being studied recently. Although baculovirus is able to rapidly express foreign proteins, it still has a low expression level. Thus, in this study, we aimed to construct a novel baculovirus inducible expression vector that not only shortens the production time of protein but also can express at a high level. The novel baculovirus inducible expression vector has been evaluated using EGFP and is expected to be a very useful tool for production of various proteins.
        4.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Arabidopsis nucleoside diphosphate kinase 2 (AtNDPK2) is an upstream signaling molecule that has been shown to induce stress tolerance in plants. In this study, the AtNDPK2 gene, under the control of a stress-inducible SWPA2 promoter, was introduced into the genome of tall fescue (Festuca arundinacea Schreb.) plants. The induction of the transgene expression mediated by methyl viologen (MV) and NaCl treatments were confirmed by RT-PCR and northern blot analysis, respectively. Under salt stress treatment, the transgenic tall fescue plants (SN) exhibited lower level of H2O2 and lipid peroxidation accumulations than the non-transgenic (NT) plants. The transgenic tall fescue plants also showed higher level of NDPK enzyme activity compared to NT plants. The SN plants were survived at 300 mM NaCl treatment, whereas the NT plants were severely affected. These results indicate that stress-inducible overexpression of AtNDPK2 might efficiently confer the salt stress tolerance in tall fescue plants.
        4,000원
        5.
        2017.04 구독 인증기관·개인회원 무료
        Metabolic resistance mechanisms of Laodelphax striatella to several insecticides, such as neonicotinoids, organophosphates and pyrethroids, have been investigated by evaluating the transcription levels of CYP450 genes. Nevertheless, no study on the CYP450-mediated carbamate resistance in L. striatella has been conducted to date. Here, we determined the transcription levels of six CYP450 genes and one carboxylesterase gene to screen detoxification genes associated with carbamate resistance. The CYP6CW1 exhibited the highest transcription level (18 fold) in a resistance strain. Interestingly, its transcription level increased slightly (3 fold) in a susceptible strain upon the exposure to a sublethal dose (LC30) of carbofuran. These results suggest that CYP6CW1 expression is inducible by carbofuran and its overexpression is likely responsible for carbofuran tolerance and resistance in L. striatella.
        6.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A nineteen years old male patient showed a cystic lesion in left maxillary canine to premolar area (#23-#25). This lesion was asymptomatic, and found during his routine radiological check in local clinic. In the radiological observation the cystic lesion showed round radiolucent image containing many calcified bodies which were usually small but irregular in shape, expanding tumorously and resulted in the displacement of canine and second premolar in the absence of first premolar. The lesion was surgically enucleated, and a cystic fibrous tissue containing abnormal teeth was removed and examined pathologically. With the histological observation of tumorous odontogenic epithelium including many ghost cells, which were closely associated with abortive teeth, the lesion was finally diagnosed as CCOT associated with complex odontoma. The ghost cells of CCOT was strongly positive for β-catenin, GADD45, and LC3, and slightly positive for MMP-9, while they were rarely positive for BCL2, Wnt1, HSP-70, and p38. Therefore, it was presumed that the ghost cells of CCOT might undergo dormant cell state through altered cytodifferentiation stimulated by severe growth arrest, DNA damage signaling, and abundant autophage formation.
        4,000원
        7.
        2016.10 구독 인증기관·개인회원 무료
        It is still challenging to establish pESCs due to differences in the genetic backgrounds of mouse, human, and pig. So it is required to find pig specific pluripotency markers and cellular signaling. In this experiments, doxycycline-inducible vectors carrying OCT4, SOX2, NANOG, KLF4 and MYC known as reprogramming factors, were infected into pig stem cells for analyzing gene expression pattern. When cultured without doxycycline, pig stem cells were stably maintained in bFGF supplemented media. However, when treated with doxycycline, pig stem cells lost alkaline phosphatase activity and were differentiated within two weeks. And then, we investigated the expression of genes related to pluripotency in doxycycline-treated pig stem cells by using qRT-PCR. The qRT-PCR data revealed that expression of OCT4, CDH1 and FUT4 were significantly increased by OCT4 overexpression and OCT4 and FUT4 were also upregulated in SOX2-infected group. When infected with combination of two factors including OCT4 or SOX2, some groups could stably maintain at LIF supplemented media, having alkaline phosphatase activity. Given these data, although ectopic gene expression induced differentiation in pig stem cells, ectopic expression of OCT4 and SOX2 could upregulate pluripotent genes and overexpreession of two factors help pig stem cells adapt LIF-contained media. This study could improve understanding of pluripotent networks as well as aid in establishing bona fide pluripotent stem cells in pig.
        8.
        2016.10 구독 인증기관·개인회원 무료
        Tet1 is well known initiatior of DNA demethylation by converting 5-methylcytosine to 5-hydroxymethylcytosine in CpG-rich regions of the brain. There have been studies using Tet1-KO mice about adult neurogenesis, cognition and memory extinction, it is still unclear whether Tet1 overexpression is beneficial for CNS networks. Thus in this study, Tet1 overexpression TG mice were developed and behavioral phenotypes were analyzed with related gene studies. Most of all, they showed anxiety-like behaviors and improved memories with increased immature neurons in the hippocampal dentate gyrus. Hence, they showed increased immediate-early gene levels (c-Fos, Arc, Egr-1, and BDNF), activation of intracellular calcium signaling (CamKII, ERK, and CREB) and changes in the expression of GABA receptor subunits (GABRA2, and GABRA4) in several brain regions. By overexpressing Tet1 in NB41A3 cells, effect of Tet1 overexpression on intracellular calcium levels with higher Egr-1 promoter activity was evaluated. These findings suggests Tet1 overexpression affects excitatory synaptic networks via activating NMDAR-dependent calcium signaling which leads to dysregulation of inhibitory synaptic networks. Also, it implies chronic and excessive activation of intraneuronal calcium signaling by Tet1 leads to behavioral differences in mice. Additionally, it suggests Tet1 overexpression in the PFC, hippocampus, and amygdala contributes as both beneficial and harmful for neural networks in differing aspects.
        11.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Oral erythroleukoplakia is characterized by severe dyskeratosis intermingled with multifocal erosive spots on the buccal mucosa, dorsal tongue, and lower lip, etc. A case of oral erythroleukoplakia was diagnosed among 83 cases of common oral leukoplakia since 1997. The pathological examination showed the typical features of leukoplakia with severe epithelial dysplasia, exhibiting dyskeratosis, acanthosis, and basal hyperplasia. The oral erythroleukoplakia was explored in comparison with a representative common oral leukoplakia by the immunohistochemical method using PCNA, β-catenin, EGFR, p53, TNFα, pAKT, and STAT3. Oral erythroleukoplakia showed strong positive reaction of PCNA, p53, EGFR, TNFα, pAKT1 and STAT3 in its spinous layer cells and these reactions were reduced in its basal layer cells, while common oral leukoplakia showed diffusely weak reaction of those proteins. Particularly, β-catenin was positive in the nuclei of some basal and spinous layer cells of oral erythroleukoplakia contrast to the common oral leukoplakia. These findings indicated that the present oral erythroleukoplakia was proliferative with the activation of β-catenin pathway, revealed the dysplastic changes of epithelium by the overexpression of EGFR, p53, and pAKT, and also produced inflammatory reaction through the activation of cytokine-dependent signalings of TNFα and STAT3. These data indicated that the present oral erythroleukoplakia might undergo the early stage of multi-step carcinogenesis via the overexpression of different oncoproteins, especially β-catenine, p53, pAKT, and STAT3.
        4,000원
        13.
        2012.10 구독 인증기관·개인회원 무료
        To identify whether higher expression of carboxylesterase (CbE) E4 in Myzus persicae is due to gene duplication, gene copy number was determined by quantitative real-time PCR. In addition, to determine the actual protein concentration of CbE E4 and it activity, Western blotting and activity staining were conducted. CbE gene copy number was highly correlated with carbamate resistance ratio (r2=0.934). However, CbE E4 expression level was little correlated with insecticide resistance ratio (r2<0.046) and no apparent correlation was observed among the gene copy number, protein quantity and total activity of CbE E4. Therefore, it was assumed that not only quantitative changing but also qualitative alteration of CbE E4 occurred in M. persicae. To investigate any potential alteration of CbE E4, mutation survey was conducted by sequencing of CbE E4 from various local strains of M. persicae. G137D and W251L mutations have been known as the main mutations associated with structural change leading to resistance. Interestingly, a new G134C mutation, which is in proximity of G137D mutation, was identified in the oxyanion hole of CbE E4. To predict the functional role of this mutation in resistance, 3-dimensional structure modeling was conducted. In summary, CbE E4 appears to be involved in resistance to both pyrethroids and carbamates as a nonspecific hydrolase or sequestration protein in M. persicae.
        14.
        2011.12 구독 인증기관 무료, 개인회원 유료
        JAZF1 (Juxtaposed with Another Zinc Finger gene 1) transcription factor are Zn-finger proteins that bind to the nuclear orphan receptor TAK/TR4 (Nakajima et al., 2004). The nuclear orphan receptor TAK1/TR4 functions as a positive as well as a negative regulator of transcription. It was recently reported that congenital cardiovascular malformations are significantly more frequent in Neurofibromatosis 1 (NF1) patients with microdeletion syndrome than in those with classical NF1. JAZF1 was expressed in adult heart of patients with microdeletion syndrome. JAZF1 is highly conserved among various species include zebrafish. We hypothesized that the expression of zebrafish Jazf1 may lead to severe forms of congenital heart disease that allow the survival of newborns and adults. In this study, we created Jazf1 transgenic zebrafish which over-express zebrafish Jazf1 cDNA under control of the CMV promoter. Our results suggested that Jazf1 expression may play an important role in zebrafish cardiac development.
        4,000원
        15.
        2011.10 구독 인증기관·개인회원 무료
        JAZF1 is a 27 kDa nuclear protein containing two putative zinc finger motifs that is associated with diabetes mellitus and prostate cancer according to genomewide association studies; however, little is known about the function of this gene in regulating metabolism. Recent evidence indicates that JAZF1 transcription factors bind to the nuclear orphan receptor TR4 and act as a strong repressor. This receptor regulates PEPCK, the key enzyme in gluconeogenesis, at the transcriptional level. Excess PEPCK expression in mice causes hyperglycemia, hyperinsulinemia, and increased glucose turnover. Therefore, we hypothesized that ectopic expression of Jazf1 may lead to abnormal expression of PEPCK that allow for the metabolic disorder. To elucidate its role in metabolism, we fed the mice with high- or normal- fat diet up to 18 weeks. In the liver tissue of mice, Jazf1 overexpression led to a substantial reduction in the expression of PEPCK. In Jazf1 overexpression mice, weight gain was found to be significantly decreased and increment of blood glucose level also decreased. Our data suggest that Jazf1 plays a critical role in the regulation of energy and lipid homeostasis, and promotes the development of metabolic disorder. Jazf1 may provide a new therapeutic target in the management of obesity, diabetes, and liver steatosis.
        18.
        2011.05 구독 인증기관·개인회원 무료
        Western blot analysis using acetylcholinesterase (AChE)-specific antibody was conducted to determine whether AChE gene (Tuace) duplication actually results in overproduction of AChE in Tetranychus urticae (TuAChE). The protein quantities of TuAChE in seven field-collected mite populations were precisely correlated with the copy numbers. To investigate the effects of each mutation on AChE insensitivity and possible fitness cost, eight variants of TuAChE were in vitro expressed using the baculovirus expression system. Kinetic analysis revealed that the Ala391Thr mutation did not change kinetic properties of AChE, whereas the Gly228Ser and Phe439Trp mutations significantly increased the insensitivity to monocrotophos. Moreover, when the Gly228Ser and Phe439Trp mutations are present together, insensitivity increased over a thousand-fold, showing that both mutations confer resistance in a synergistic manner. Presence of the mutations, however, reduced catalytic efficiency of AChE considerably, suggesting an apparent fitness cost in monocrotophosresistant mites. Reconstitution of the multiple copies of AChE having different compositions of mutations revealed that the catalytic efficiencies of the six-copy and two-copy AChEs (resembling the AD and PyriF strains of mite, respectively) were still lower but comparable to that of wildtype AChE. These finding clearly suggested that multiple rounds of Tuace duplication was needed to compensate the reduced catalytic activity of AChE caused by mutations.
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