• Journal of Radiation Protection and Research
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• v.30 no.4
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• pp.197-208
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• 2005

Although little information is available on the underlying mechanisms, various genetic factors have been associated with tissue-specific responses to radiation. In the present study, we explored the possibility whether organ specific gene expression is associated with radiosensitivity using samples from brain, lung and spleen. We examined intrinsic expression pattern of 23 genes in the organs by semi-quantitative RT-PCR method using both male and female C57BL/6 mice. Expression of p53 and p21, well known factors for governing sensitivity to radiation or chemotherapeutic agents, was not different among the organ types. Both higher expression of sialyltransferase, delta7-sterol reductase, leptin receptor splice variant form 12.1, and Cu/Zn superoxide dismutase (SOD) and lower expression of alphaB crystalline were specific for spleen tissue. Expression level of glutathione peroxidase and APO-1 cell surface antigen gene in lung tissue was high, while that of Na, K-ATPase alpha-subunit, Cu/ZnSOD, and cyclin G was low. Brain, radioresistant organ, showed higher expressions of Na, K-ATPase-subunit, cyclin G, and nucleolar protein hNop56 and lower expression of delta7-sterol reductase. The result revealed a potential correlation between gene expression patterns and organ sensitivity, and Identified genes which might be responsible for organ sensitivity.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.59-60
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• 2000

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.9-19
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• 2003

Pig organ is thought to be the most suitable nonhuman organ for xenotransplanstation. However, one of the major constraints to using pig organs for xenotransplantation is human natural antibody-mediated hyperacute rejection (HAR). Elimination of a(1,3) galactosyltransferase (GGTA1) from the pig is expected to be a solution to the problem of hyperacute rejection. Many efforts have made characterization of GGTA1 in structure and function, improvement in the technique of DNA transfection of somatic cells and advancement of the pig NT, a specific modification has been made to one copy of the GGTAl gene by Missouri group in 2002 To date because homozygousity of the genetic modification has been achieved in this gene, the role of gala(1,3) gal specific natural antibody in HAR and the efficacy of xenotransplantation in a nonhuman primate model will be addressed. Of other genes are found to be involved in rejection of pig donors by primates, the technology will be available to modify those genes so that rejection can be overcome.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.9-19
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• 2003

Pig organ is thought to be the most suitable nonhuman organ for xenotransplanstation. However, one of the major constraints to using pig organs for xenotransplantation is human natural antibody-mediated hyperacute rejection (HAR). Elimination of a(1,3) galactosyltransferase (GGTA1) from the pig is expected to be a solution to the problem of hyperacute rejection. ry1any efforts have made characterization of GGTA1 in structure and function. improvement in the technique of DNA transfection of somatic cells and advancement of the pig NT, a specific modification has been made to one copy of the GGTA1 gene by Missouri group in 2002. To date because homozygousity of the genetic modification has been achieved in this gene, the role of gala(1,3) gal specific natural antibody in HAR and the efficacy of xenotransplantation in a nonhuman primate model will be addressed. If other genes are found to be involved in rejection of pig donors by primates, the technology will be available to modify those genes so that rejection can be overcome.

• Molecules and Cells
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• v.25 no.3
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• pp.358-367
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• 2008

The embryonic germ cell (EGCs) of mice is a kind of pluripotent stem cell that can be generated from pre- and post-migratory primordial germ cells (PGCs). Most previous studies on DNA methylation of EGCs were restricted to 12.5 days post coitum (dpc). This study was designed to establish and characterize murine EGC lines from migrated PGCs as late as 13.5 dpc and to estimate the degrees of methylation of their imprinted genes as well as of the non-imprinted locus, Oct4, using an accurate and quantitative method of measurement. We established five independent EGC lines from post migratory PGCs of 11.5-13.5 dpc from C57BL/6 ${\times}$ DBA/2 F1 hybrid mouse fetuses. All the EGCs exhibited the typical features of pluripotent cells including hypomethylation of the Oct4 regulatory region. We examined the methylation status of three imprinted genes; Igf2, Igf2r and H19 in the five EGC lines using bisulfite genomic sequencing analysis. Igf2r was almost unmethylated in all the EGC lines irrespective of the their sex and stage of isolation; Igf2 and H19 were more methylated than Igf2r, especially in male EGCs. Moreover, EGCs derived at 13.5 dpc exhibited higher levels of DNA methylation than those from earlier stages. These results suggest that in vitro derived EGCs acquire different epigenotypes from their parental in vivo migratory PGCs, and that sex-specific de novo methylation occurs in the Igf2 and H19 genes of EGCs.

• Journal of Photoscience
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• v.12 no.3
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• pp.163-169
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• 2005

Recent reports suggest that floral organs such as sepals, petals, stamens, and carpels are specified by quaternary MADS protein complexes with different combinations. The formation of quaternary complexes of ABCDE MADS proteins may be the molecular basis of ABCDE model for the floral organ development. The MADS complexes involved in each floral organ development seem to be conserved in at least dicot species although detailed molecular mechanism is slightly different depending on species. Even in monocot, at least rice, MADS complexes similar to those in dicot exist, suggesting that the floral organ specification by MADS protein complexes may be conserved in most of plants. The MADS protein complexes may have more specific recognition of target genes or more transcription activation ability than monomers or dimers, resulting in finely regulated floral organ development.

• BMB Reports
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• v.46 no.7
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• pp.338-345
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• 2013

microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by targeting the 3'-untranslated region of multiple target genes. Pathogenesis results from defects in several gene sets; therefore, disease progression could be prevented using miRNAs targeting multiple genes. Moreover, recent studies suggest that miRNAs reflect the stage of the specific disease, such as carcinogenesis. Cystic diseases, including polycystic kidney disease, polycystic liver disease, pancreatic cystic disease, and ovarian cystic disease, have common processes of cyst formation in the specific organ. Specifically, epithelial cells initiate abnormal cell proliferation and apoptosis as a result of alterations to key genes. Cysts are caused by fluid accumulation in the lumen. However, the molecular mechanisms underlying cyst formation and progression remain unclear. This review aims to introduce the key miRNAs related to cyst formation, and we suggest that miRNAs could be useful biomarkers and potential therapeutic targets in several cystic diseases.

• Biomedical Science Letters
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• v.9 no.1
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• pp.1-8
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• 2003

Liver is an organ having an ability to regenerate by itself when it is damaged or removed. Since the research on the liver regeneration so far was regarding on the cellular multiplications not the formation of the shape, we intended to analyze the expression pattern of Hox genes during liver regeneration. RNA samples isolated from liver at the time of partial hepatectomy, 4 hours as well as 3 days later following regeneration were used to perform RT-PCR with Hox-specific degenerate primers. The PCR products were cloned, sequenced and analyzed through BLAST program. Genes belonging to the AbdB type Hox genes (paralogous groups IX-XIII) expressed predominantly during regeneration, while the other group (I-VII), especially Hoxal and bl seemed to be expressed continuously before and after regeneration. These data altogether imply that paralogous group IX and X genes including Hoxa10 and d10 seemed to be regeneration specific genes of liver.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.271-286
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• 2017

GROWTH-REGULATING FACTOR (GRF) genes encode plant-specific transcription factors containing two conserved QLQ and WRC domains and play critical roles in regulating the growth and development of lateral organs, such as cotyledons, leaves, and flowers. To explore the agricultural potential of Brassica rapa GRF genes (BrGRFs), the researchers isolated seven BrGRFs (BrGRF3-1, 3-2, 5, 7, 8-1, 8-2, and 9) and constructed BrGRF-overexpressing Arabidopsis thaliana plants (BrGRF-OX). BrGRF-OX plants developed larger cotyledons, leaves, and flowers as well as longer roots than the wild type. The increase in size of these organs were due to increases in cell number, but not due to cell size. BrGRF-OX plants also had larger siliques and seeds. Furthermore, BrGRF-OX seeds produced more oil than the wild type. RT-PCR analysis revealed that BrGRFs regulated expression of a wide range of genes that are involved in gibberellin-, auxin-, cell division-related growth processes. Taken together, the data indicates that BrGRFs act as positive regulators of plant growth, thus raising the possibility that they may serve as a useful genetic source for crop improvement with respect to organ size and seed oil production.

• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.176-182
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• 1994

The light-organ symbiont of pine cone fish, Vibrio fischeri, senses its presence in the host and responds to environmental changes by differentially expressing its symbiosis-related luminescence genes. The V. fischeri luminescence genes are activated by LuxR protein in the presence of an autoinducer. In an effort to elucidate the mechanism of regulation of luxR, a plasmid containing luxR was mutagenized in vitro with hydroxylamine and a luxR mutant plasmid was isolated by its ability to activate luminescence genes cloned in E. coli in the absence of the autoinducer. The specific base change identified by DNA sequencing was only single base transition at ＋78 from the transcriptional start of luxR. Based on a Western immunoblot analysis, the nucleotide change directed the synthesis of much higher level of LuxR protein without any amino acid substitutions. The results suggest that the region including the ＋78th base is presumably internal operator required for autorepression of luxR, and the increased cellular level of LuxR results in activation of luminescence genes by autoinducer independent fashion.