• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.624-627
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• 2003

Benzo[a]pyrene (B[a]P) is an environmental pollutant that has been implicated in carcinogenesis. Saccharomyces cerevisiae was treated with B[a]P, and the responses of its cytochrome P450 (CYP) enzyme and DNA-damage checkpoint genes were examined through gene expression profiles using a reverse transcription polymerase chain reaction (RT-PCR). The DNA-damage checkpoint genes tested were the chk1 and pds1 genes, involved in a metaphase arrest, the swi6 gene targeted by G1 arrest, the pol2 gene related to S phase arrest, and the cln2 gene encoding a cyclin protein, all of which are based on rad9 and rad24. Among these genes, no noticeable effect was found when the cells were exposed to various concentrations of B[a]P. However, the transcriptional activity of CYP51 was significantly different when the cells were exposed to B[a]P. Accordingly, the present results indicate that cytochrome P450 plays a more significant role than DNA-damage checkpoint genes in the response of S. cerevisiae to B[a]P.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.09a
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• pp.39-39
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• 2005

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.211.4-211
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• 2003

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.195.3-195
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• 2003

No Abstract, See Full Text

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.154-160
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• 2015

The plant breeding technology was developed with genetic engineering. Many researchers and breeders have turned from traditional breeding to molecular breeding. Genetically modified organisms (GMO) were developed via molecular breeding technology. Currently, molecular breeding technologies facilitate efficient plant breeding without introducing foreign genes, in virtue by of gene editing technology. Gene targeting (GT) via homologous recombination (HR) is one of the best gene editing methods available to modify specific DNA sequences in genomes. GT utilizes DNA repair pathways. Thus, DNA repair systems are controlled to enhance HR processing. Engineered sequence specific endonucleases were applied to improve GT efficiency. Engineered sequence specific endonucleases like the zinc finger nuclease (ZFN), TAL effector nuclease (TALEN), and CRISPR-Cas9 create DNA double-strand breaks (DSB) that can stimulate HR at a target site. RecQl4, Exo1 and Rad51 are effectors that enhance DSB repair via the HR pathway. This review focuses on recent developments in engineered sequence specific endonucleases and ways to improve the efficiency of GT via HR effectors in plants.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.223-228
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• 2002

We have developed a homemade particle inflow gun (PIG) system which has simple operation method, low price and high gene introduction efficiency into rice callus. Rice callus were inflowed with gold particles containing DNA of a plasmid, pIG121Hm, harboring intron GUS ($\beta$-glucuronidase) gene, NPTII gene and HPT gene. For optimal GUS transient expression, the effects of parameters on DNA delivery efficiency of the PIG system was investigated by scoring transient GUS expression. The highest number of blue spots was observed at 16 mM of spemidine and 1.5 M of calcium chloride, respectively. And the amount of gold particles required for the best GUD expression was 2 mg. Optimum GUS transient expression was observed at target distance of 12 cm and helium pressure of 3.5 bar (50 psi). Gene introduction efficiency of the PIG system was observed almost similar to that of the Biolistic Gun (Bio-Rad Company). Since PIG system is simple to operate and one doesn't need disposable accessaries, the PIG system can be easily applied to various replication experiments.

• The Korean Journal of Nuclear Medicine
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• v.34 no.2
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• pp.144-153
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• 2000

Purpose: The purpose of this study was to evaluate the relationship between radiation-induced activation of DNA repair genes and radiation induced apoptosis in A431 cell line. Materials and Methods: Five and 25 Gys of gamma radiation were given to A431 cells by a Cs-137 cell irradiator. Apoptosis was evaluated by flow cytometry using annexin V-fluorescein isothiocyanate and propidium iodide staining. The expression of DNA repair genes was evaluated by both Northern and Western blot analyses. Results: The number of apoptotic cells increased with the increased radiation dose. It increased most significantly at 12 hours after irradiation. Expression of p53, p21, and hRAD50 reached the highest level at 12 hours after 5 Gy irradiation. In response to 25 Gy irradiation, hRAD50 and p21 were expressed maximally at 12 hours, but p53 and GADD45 genes showed the highest expression level after 12 hours. Conclusion: Induction of apoptosis and DNA repair by ionizing radiation were closely correlated. The peak time of inducing apoptosis and DNA repair was 12 hours in this study model. hRAD50, a recently discovered DNA repair gene, was also associated with radiation-induced apoptosis.

• Animal cells and systems
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• v.3 no.4
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• pp.413-415
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• 1999

Our previous report demonstrated that the rhp51$^＋$, a recA and RAD51 homolog of the fission yeast, encodes three transcripts of 1.9, 1.6 and 1.3 kb which have at least six polyadenylation sites. The 3'-end of the gene alone can direct the formation of multiple, discrete 3'ends of the transcripts. To identify the regulatory element required for the 3'-end formation of -rhp51$^＋$ deletion mapping analysis was performed. Northern blot analysis revealed that the 254-bp DNA fragment including 4 distinct poly (A) sites downstream from the Hindlll site, is crucial for normal 3'-end formation. Deletion of the 3'-terminal AU rich region caused appearance of read-through RNA, leading to enhancement of survival rate of the rhp51 deletion mutant in response to DNA damaging agent, methylmethane sulfonate (MMS). The results imply that the rhp51$^＋$ system may be useful for molecular analysis of the 3'-end formation of RNA in the fission yeast.

• Journal of Animal Science and Technology
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• v.52 no.4
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• pp.329-336
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• 2010

Myogenic satellite cells (MSCs) are mononuclear, multipotent progenitors of adult skeletal muscle possessing a capacity of forming adipocyte-like cells (ALC). To identify the skeletal muscle type-specific myogenic and adipogenic genes during MSCs differentiation, total RNA was extracted from bovine MSCs, myotube-formed cell (MFC), and ALC from each of Beef shank, Longissimus dorsi, Deep pectoral, and Semitendinosus. DNA microarray analysis (24,000 oligo chip) comparing MSCs with MFC and ALC, respectively, revealed 135 differentially expressed genes (> 4 fold) among four cuts. Real-time PCR confirmed expression of 29 genes. Furthermore, the whole tissue sample RNAs analysis showed 6 differentially expressed genes in Beef shank. Among which, 1 gene in MSCs, 4 in MFC, and 1 in ALCs were highly expressed. This study will provide an insight for better understanding the molecular mechanism of differentiation of skeletal muscle type-specific MSCs. The identified genes may be used as marker to distinguish skeletal muscle types.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.99-109
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• 1999

Enteropathogenic Yersina enterocolitica is an important cause of human and animal disease. Phenotypic and genotypic characteristics currently used to identify Yersinia enterocolitica are not necessarily sufficient to differentiate pathogenic from non-pathogenic strains or to analyze the epidemiology of yersiniae at a molecular level. To improve the characterization of Yersinia enterocolitica, A total of 65 isolates of Yersinia enterocolitica were examined with bioserotyping, antibiotic susceptibilities, PFGE, PCR-ribotyping. Genomic DNA pattern generated by PFGE are highly specific for different strains of an organism and have significant value in epidemiologic investigations. The PFGE analysis of Not I-digested chromosomal DNA of Y. enterocolitica were performed with a CHEF Mapper(Bio-Rad, USA). Not I generated 19 restriction endonuclease digestion profiles(REDP). PCR-ribotyping, performed with primers complementry to conserved regions of 16S and 23S rRNA gene, generated 13 ribotypes. PCR-ribotyping can be considered a good technich for subtyping strains of Y.enterocolitica.