• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.62-72
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• 2002

This study has investigated the biosynthesis and function of the heavy metal binding peptides, the phytochelatins, in plants. PCs are synthesised enzymatically from glutathione by the enzyme PC synthase in the presence of heavy metal ions. Using Arabidopsis thaliana as a model organism cadmium-sensitive, phytochelatin-deficient mutants have been isolated and characterised in previous studies. The cadl mutants have wildtype levels of glutathione, are PC deficient and lack PC synthase activity. Thus, the CADl gene has been proposed to encode PC synthase. The CADl gene was isolated by a positional cloning strategy The gene was mapped and a candidate identified. Each of four cadl mutants had a single base pair change in the candidate gene and the cadmium-sensitive, cadl phenotype was complemented by the candidate gene. This demonstrated the CADl gene had been cloned. A homologous gene in the fission yeast, Schizosaccharomyces pombe was identified through database searches. A targeted-deletion mutation of this gene was constructed and the mutant, like cadl mutants of Arabidopsis, was cadmium-sensitive and PC-deficient. A comparison of the redicted amino acid sequences reveals a highly conserved N-terminal region Presumed to be the catalytic domain and a variable C-terminal region containing multiple Cys residues proposed to be involved in activation of the enzyme by metal ions. Similar genes were also identified in animal species. The Arabidopsis CADl/AtPCSl and S. pombe SpbPCS genes were expressed in E. coli and were shown to be sufficient for glutathione-dependent, heavy metal activate PC synthesis in vitro, thus demonstrating these genes encode PC synthase enzymes. Using RT-PCR, AtPCSl expression appeared to be independent of Cd exposure. However, at higher levels of Cd exposure a AtPCSl-CUS reporter gene construct appeared to be more highly expressed. Using the reporter gene construct, AtPCSl was expressed most tissues. Expression appeared to be greater in younger tissues and same higher levels of expression was observed in some regions, including carpels and the base of siliques. AtPCS2 was a functional gene encoding an active PC synthase. However, its Pattern of expression and the phenotype of a mutant (or antisense line) have not been determined. Assuming the gene is functional then it has clearly been maintained through evolution and must provide some selective advantage. This implies that, at least in some cells or tissue, it is likely to be the dominant PC synthase expressed. This remains to be determined

• International Journal of Oral Biology
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• v.32 no.4
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• pp.119-125
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• 2007

Dlx3 is a homeodomain protein and is known to play a role in development and differentiation of many tissues. Deletion of four base pairs in DLX3 (NT3198) is causally related to tricho-dento-osseous (TDO) syndrome (OMIM #190320), a genetic disorder manifested by taurodontism, hair abnormalities, and increased bone density in the cranium. The molecular mechanisms that explain the phenotypic characteristics of TDO syndrome have not been clearly determined. In this study, we examined phenotypic characteristics of wild type DLX3(wtDlx3) and 4-BP DEL DLX3 (TDO mtDlx3) in C2C12 cells. To investigate how wtDlx3 and TDO mtDlx3 differentially regulate osteoblastic differentiation, reporter assays were performed by using luciferase reporters containing the promoters of alkaline phosphatase, bone sialoprotein or osteocalcin. Both wtDlx3 and TDO mtDlx3 enhanced significantly all the reporter activities but the effect of mtDlx3 was much weaker than that of wtDlx3. In spite of these differences in reporter activity, electrophoretic mobility shift assay showed that both wtDlx3 and TDO mtDlx3 formed similar amounts of DNA binding complexes with Dlx3 binding consensus sequence or with ALP promoter oligonucleotide bearing the Dlx3 binding core sequence. TDO mtDlx3 exhibits a longer half-life than wtDlx3 and it corresponds to PESTfind analysis result showing that potential PEST sequence was missed in carboxy terminal of TDO mtDlx3. In addition, co-immunoprecipitation demonstrated that TDO mtDlx3 binds to Msx2 more strongly than wtDlx3. Taken together, though TDO mtDlx3 acted as a weaker transcriptional activator than wtDlx3 in osteoblastic cells, there is possibility that during in vivo osteoblast differentiation TDO mtDlx3 may antagonize transcriptional repressor activity of Msx2 more effectively and for longer period than wtDlx3, resulting in enhancement of osteoblast differentiation.

• Journal of Digital Convergence
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• v.18 no.7
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• pp.357-368
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• 2020

This study identifies the aspects and characteristics of 'Digital Sexual Crimes' that changed rapidly in recent years. It has identified the so-called "Telegram sexual harassment and exploitation" incident on the front page. We also want to analyze this and draw up policy suggestions that can help prepare social measures. In the wake of the Telegram sexual exploitation scandal, The National Assembly is quickly proposing related bills. However, the reality is that even a clear concept and definition of "Digital sexual Crimes" have not been made yet. The effective support system for victims is also insufficient. Therefore, this paper examines the definition and concept of child sexual exploitation and harassment. We will look at the features, causes, and conditions. In addition, it will examine the current status of Digital Sexual Crimes distribution and deletion of domestic, foreign platforms. Major foreign countries, including the U. S. A. refer to cases in which big data and artificial intelligence technologies are actively used to protect victims and track perpetrators.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.91-97
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• 2018

The evolutionally conserved TREX complex member, Yra1/ALY, belongs to the REF (RNA and export factor binding proteins) family of hnRNP-like proteins, which has been implicated in multiple processes including transcription, nuclear RNA stability, and mRNA export. Fission yeast, Schizosaccharomyces pombe, genome encodes two members of REF proteins. In addition to Mlo3 known previously as an mRNA export factor, there is the other REF protein, Tho4, which is predicted as a component of THO complex. Here we showed that deletion of tho4 (SPBC106.12c) gene does not inhibit both growth and nuclear mRNA export. However, overexpression of tho4 displays growth retardation and slight accumulation of $poly(A)^+$ RNA in the nucleus. Neither ${\Delta}tho4$ ${\Delta}mlo3$ nor ${\Delta}tho4$ ${\Delta}mex67$ double mutants exhibit additive growth defect. Moreover, yeast two-hybrid and co-immunoprecipitation analysis did not show that the Tho4 protein interacted with any members of TREX complex and mRNA export factor Rae1. Contrary to expectation, these observations support that the S. pombe Tho4 is not a component of TREX complex, and not directly involved in bulk mRNA export from the nucleus.

• Tuberculosis and Respiratory Diseases
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• v.70 no.1
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• pp.21-27
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• 2011

Background: Although the gold standard method for research trials on epidermal growth factor receptor (EGFR) mutations has been direct sequencing, this approach has the limitations of low sensitivity and of being time-consuming. Peptide nucleic acid (PNA)-mediated polymerase chain reaction (PCR) clamping is known to be a more sensitive detection tool. The aim of this study was to compare the detection rate of $EGFR$ mutation and EGFR-tyrosine kinase inhibitor (TKI) responsiveness according to $EGFR$ mutation status using both methodologies. Methods: Clinical specimens from 112 NSCLC patients were analyzed for $EGFR$ mutations in exons 18, 19, 20, and 21. All clinical data and tumor specimens were obtained from 3 university hospitals in Korea. After genomic DNA was extracted from paraffin-embedded tissue specimens, both PNA-mediated PCR clamping and direct-sequencing were performed. The results and clinical response to $EGFR$-TKIs were compared. Results: Sequencing revealed a total of 35 (22.9%) mutations: 8 missense mutations in exon 21 and 26 deletion mutations in exon 19. PNA-mediated PCR clamping showed the presence of genomic alterations in 45 (28.3%) samples, including the 32 identified by sequencing plus 13 additional samples (6 in exon 19 and 7 in exon 21). Conclusion: PNA-mediated PCR clamping is simple and rapid, as well as a more sensitive method for screening of genomic alterations in $EGFR$ gene compared to direct sequencing. This data suggests that PNA-mediated PCR clamping should be implemented as a useful screening tool for detection of $EGFR$ mutations in clinical setting.

• Journal of Embryo Transfer
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• v.29 no.4
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• pp.339-344
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• 2014

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein (Cas9) system can be applied to produce transgenic pigs. Therefore, we applied CRISPR/Cas9 system to generate FoxN1-targeted pig parthenogenetic embryos. Using single guided RNA targeted to pig FoxN1 genes was injected into cytoplasm of in vitro matured oocyte before electrical activation. In results, regardless of the concentrations of vector, the cleavage rate were significantly (p<0.05) decreased ($4ng/{\mu}l$, 51.24%; $8ng/{\mu}l$, 40.88%; and $16ng/{\mu}l$; 45.22%) compared to no injection group (70.44%). The blastocyst formation rates were also decreased in vector injected 3 groups ($4ng/{\mu}l$, 7.96%; $8ng/{\mu}l$, 6.4%; and $16ng/{\mu}l$; 9.04%) compared to no injection group (29.07%). In addition, the blastocyst formation rates between sham injected group (13.51%) and no injection group (29.07%) also showed significant difference (p<0.05). The mutation rates were comparable between groups ($4ng/{\mu}l$, 18.4%; $8ng/{\mu}l$, 12.5%; and $16ng/{\mu}l$; 20.0%). The sequencing analysis showed that blastocysts derived from each group were successfully mutated in FoxN1 loci regardless of the vector concentrations. However, the deletion patterns were higher than the patterns of point mutation and insertion regardless of the vector concentrations. In conclusion, we described that cytoplasmic microinjection of FoxN1-targeted CRISPR/Cas9 vector could efficiently generate transgenic pig parthenogenetic embryos in one-step.

• Journal of Genetic Medicine
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• v.4 no.1
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• pp.80-83
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• 2007

A 36-year-old pregnant woman was referred for amniocentesis at 19.5 weeks gestation because of advanced maternal age and evidence of increased risk for Edward syndrome in the maternal serum screening test. Cytogenetic analysis of the cultured amniotic fluid cells revealed mosaicism for ring chromosome 11: 46,XX,r(11)[65]/ 45,XX,-11[16]/ 46,XX [34]. Parental karyotypes were normal. A targeted ultrasound showed intrauterine grow th restriction (IUGR). Cordocentesis was performed to characterize the ring chromosome and to rule out tissue specific mosaicism. Karyotype was confirmed as 46,XX,r(11) (p15.5q24.2)[229]/45,XX,-11[15]. And a few new form of ring w ere detected in this culture. The deletion of subtelomeric regions in the ring chromosome were detected by fluorescent in situ hybridization (FISH). The pregnancy was terminated. The fetal autopsy showed a growth-retarded female fetus with rocker bottom feet. We report a case of prenatally detected a de novo ring chromosome 11.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.292-296
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• 2017

In eukaryote, THO/TREX complex plays a critical role in transcriptional elongation, pre-mRNA processing, and nuclear mRNA export. This complex is evolutionally well- conserved, but there are some differences in composition and function according to organisms. Here we showed that spTex1, a component of THO/TREX complex, is not essential for growth and mRNA export in a fission yeast, Schizosaccharomyces pombe, which is more similar to higher eukaryote than budding yeast. Deletion and overexpression of the spTex1 gene do not lead to any detectable growth phenotype and accumulation of poly(A)+ RNA in the nucleus. And the spTex1-GFP protein is localized mainly in the nucleus. Yeast two-hybrid and Co-immunoprecipitation analysis showed that the spTex1 protein interacted with spHpr1 (THOC1) and spTho2 (THOC2), main subunits of THO complex. We conclude that the S. pombe Tex1 is a component of THO/TREX complex, but does not plays important roles in growth and bulk mRNA export from the nucleus.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.1
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• pp.77-91
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• 2019

Recent Linux operating systems having been increasingly used, ranging from automotive consoles, CCTV, IoT devices, and mobile devices to various versions of the kernel. Because these devices can be used as strong evidence in criminal investigations, there is a risk of destroying evidence through file deletion. Ext filesystem forensics has been studied in depth because it can recovery deleted files without depending on the kind of device. However, studies have been carried out without consideration of characteristics of file system which may vary depending on the kernel. This problem can lead to serious situations, such as those that can impair investigative ability and cause doubt of evidence ability, when an actual investigation attempts to analyze a different version of the kernel. Because investigations can be performed on various distribution and kernel versions of Linux file systems at the actual investigation site, analysis of the metadata changes that occur when files are deleted by Linux distribution and kernel versions is required. Therefore, in this paper, we analyze the difference of metadata according to the Linux kernel as a solution to this and recovery deleted file. After that, the investigating agency needs to consider the metadata change caused by the difference of Linux kernel version when performing Ext filesystem forensics.

• Journal of Life Science
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• v.33 no.1
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• pp.34-42
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• 2023

In a signal transduction network, from the perception of stress signals to stress-responsive gene ex- pression, binding of various transcription factors to cis-acting elements in stress-responsive promoters coordinate the adaptation of plants to abiotic stresses. Among the AP2/ERF transcription factor family genes, group VII ERF genes, such as RAP2.12, RAP2.2, RAP2.3, AtERF73/HRE1, and AtERF71/ HRE2, are known to be involved in the response to hypoxia stress in Arabidopsis. In this study, we dissected the HRE1 promoter to identify hypoxia-responsive region(s). The 1,000 bp upstream promoter region of HRE1 showed increased promoter activity in Arabidopsis protoplasts and transgenic plants under hypoxia conditions. Analysis of the promoter deletion series of HRE1, including 1,000 bp, 800 bp, 600 bp, 400 bp, 200 bp, 100 bp, and 50 bp upstream promoter regions, using firefly luciferase and GUS as reporter genes indicated that the -200 to -100 region of the HRE1 promoter is responsible for the transcriptional activation of HRE1 in response to hypoxia. In addition, we identified two putative hypoxia-responsive cis-acting elements, the ERF-binding site and DOF-binding site, in the -200 to -100 region of the HRE1 promoter, suggesting that the expression of HRE1 might be regulated via the ERF transcription factor(s) and/or DOF transcription factor(s). Collectively, our results suggest that HRE1 contains hypoxia-responsive cis-acting elements in the -200 to -100 region of its promoter.