• Asian-Australasian Journal of Animal Sciences
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• 제16권12호
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• pp.1837-1841
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• 2003

In an attempt to isolate novel molecules that may play a regulatory role in adipocyte differentiation, we devised an experimental strategy to identify adipose tissue-specific genes by modifying cDNA microarray technique. We used genefilter membranes containing approximately 15,000 rat non-redundant EST clones of which 4,000 EST were representative clones of known genes and 11,000 ESTs were uncharacterized clones. A series of hybridization of genefilter membranes with cDNA probes prepared from various rat tissues and nucleic acids sequence analysis allowed us to identify two adipose-tissue specific genes, adipocyte-specific secretory factor (ADSF) and H-rev107. Verification of tissue-specific expression patterns of these two genes by Northern blot analysis showed that ADSF mRNA is exclusive expressed in adipose tissue and the H-rev107 mRNA is predominantly expressed in adipose tissue. Further analysis of gene expression of ADSF and H-rev107 during 3T3-L1 adipocyte differentiation revealed that the ADSF and H-rev107 gene expression patterns are closely associated with the adipocyte differentiation program, indicating their possible role in the regulation of adipose tissue development. Overall, we demonstrated an application of modified cDNA microarray technique in molecular cloning, resulting in identification of two novel adipose tissue-specific genes. This technique will also be used as a useful tool in identifying novel genes expressed in a tissue-specific manner.

• Genomics & Informatics
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• 제2권2호
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• pp.92-98
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• 2004

A cDNA microarray experiment is one of the most useful high-throughput experiments in medical informatics for monitoring gene expression levels. Statistical analysis with a cDNA microarray medical data requires a normalization procedure to reduce the systematic errors that are impossible to control by the experimental conditions. Despite the variety of normalization methods, this. paper suggests a more general and synthetic normalization algorithm with a control gene set based on previous studies of normalization. Iterative normalization method was used to select and include a new control gene set among the whole genes iteratively at every step of the normalization calculation initiated with the housekeeping genes. The objective of this iterative normalization was to maintain the pattern of the original data and to keep the gene expression levels stable. Spatial plots, M&A (ratio and average values of the intensity) plots and box plots showed a convergence to zero of the mean across all genes graphically after applying our iterative normalization. The practicability of the algorithm was demonstrated by applying our method to the data for the human photo aging study.

• Journal of Pharmacopuncture
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• 제11권4호
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• pp.5-14
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• 2008

Objective This study was undertaken to determine the effect of Whallak-tang on expression of CD/cytokine Genes. Methods The expression of CD/Cytokine Genes were examined by cDNA microarray using the human mast cell line(HMC-1). Results The expression of ATP5F1, FLJ20671, unknown, KIAA0342, OAS2, unknown genes were increased in $200{\sim}300%$ range. The expression of unknown, MDS006, IFITM1, MRPL3, ZNF207, FTH1, FBP1, NRGN, NR1H2, KIAA0747 genes were decreased in $0{\sim}33%$ range. Conclusion These results would provide important basic data on the possibility of the clinical treatment of Whallak-tang in musculoskeletal disease.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.945-951
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• 2007

DNA-DNA hybridization has been established as an important technology in bacterial species taxonomy and phylogenetic analysis. In this study, we analyzed how the efficiency with which the genomic DNA from one species hybridizes to the genomic DNA of another species (DNA-DNA hybridization) in microarray analysis relates to the similarity between two genomes. We found that the predicted DNA-DNA hybridization based on genome sequence similarity correlated well with the experimentally determined microarray hybridization. Between closely related strains, significant numbers of highly divergent genes (>55% identity) and/or the accumulation of mismatches between conserved genes lowered the DNA-DNA hybridization signal, and this reduced the hybridization signals to below 70% for even bacterial strains with over 97% 16S rRNA gene identity. In addition, our results also suggest that a DNA-DNA hybridization signal intensity of over 40% indicates that two genomes at least shared 30% conserved genes (>60% gene identity). This study may expand our knowledge of DNA-DNA hybridization based on genomic sequence similarity comparison and further provide insights for bacterial phylogeny analyses.

• Microbiology and Biotechnology Letters
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• 제44권4호
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• pp.563-570
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• 2016

Two Streptomyces griseus strains, a wild-type strain and an A-factor-dependent transcriptional activator mutant strain harboring multiple copies of a gene, dasA, that encodes a substrate-binding protein of the ATP-binding cassette transporter, showed severe ectopic sporulation of young substrate hyphae in response to glucose. The effect of dasA overexpression on the ectopic sporulation of Streptomyces strains was evaluated by comparing the transcriptomes of the strain harboring multiple copies of dasA and a strain harboring empty vector. By DNA microarray, 4 genes (SGR794, SGR2469, SGR3656, and SGR3657) and 3 clusters (SGR795-797, SGR2377-2378, and SGR6997-6998) were differentially expressed by more than 2-fold in S. griseus strains harboring dasA. The DNA microarray result was validated by low-resolution S1 nuclease mapping.

• Asian-Australasian Journal of Animal Sciences
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• 제21권1호
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• pp.11-18
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• 2008

We created a cDNA microarray representing approximately 3,500 pig genes for functional genomic studies. The array elements were selected from 6,494 cDNA clones identified in a large-scale expressed sequence tag (EST) project. These cDNA clones came from normalized and subtracted porcine adipose tissue cDNA libraries. Sequence similarity searches of the 3,426 ESTs represented on the array using BLASTN identified 2,790 (81.4%) as putative human orthologs, with the remainder consisting of "novel" genes or highly divergent orthologs. We used the gene microarray to profile transcripts expressed by adipose tissue of fatty Chinese Xiang pig (XP) and muscley Large White (LW). Microarray analysis of RNA extracted from adipose tissue of fatty XP and muscley LW identified 81 genes that were differently expressed two fold or more. Transcriptional differences of four of these genes, adipocyte fatty acid binding protein (aP2), stearyl-CoA desaturase (SCD), sterol regulatory element binding transcription factor 1 (SREBF1) and lipoprotein lipase (LPL) were confirmed using SYBR Green quantitative RT-PCR technology. Our results showed that high expression of SCD and SREBF1 may be one of the reasons that larger fat deposits are observed in the XP. In addition, our findings also illustrate the potential power of microarrays for understanding the molecular mechanisms of porcine development, disease resistance, nutrition, fertility and production traits.

• Proceedings of the Korean Information Science Society Conference
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• 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (A)
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• pp.955-957
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• 2004

DNA 마이크로어레이(microarray)란 새로운 개념의 기술이 도입되면서, 이를 이용하여 유전체(genome)를 탐색하거나, 동시에 수천 개의 유전자간의 상호작용을 관찰 할 수 있게 되었다. 이러한 이점으로 인하여, 많은 DNA 마이크로어레이 실험이 시행되고 있다. DNA 마이크로어레이 실험으로 생성되는 이미지 데이터는 그 양이 방대하고, 분석하는 연구자에 따라 판정이 달라질 수 있으므로, 이를 효율적으로 분석할 수 있는 방법들이 필요하게 되었다. 하지만, 마이크로어레이 이미지 데이터는 반점(Spot) 위치의 변동이나 반점의 모양, 크기가 고르지 않는 것과 칼은 다양한 문제로 인하여 자동적으로 분석하기는 어렵다. 본 논문에서는 마이크로어레이의 균일 격자(regular grid) 구조 탐색을 이용하여 새로운 주소 결정 알고리즘을 소개한다.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 한국생물정보시스템생물학회 2001년도 제2회 생물정보 워크샵 (DNA Chip Bioinformatics)
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• pp.97-115
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• 2001

cDNA microarray technology allows the monitoring of expression levels for thousands of genes simultaneously. Many statistical analysis tools become widely applicable to the analysis of cDNA microarray data. In this talk, we consider a two-way ANOVA model to differentiate genes that have high variability and ones that do not. Using this model, we detect genes that have different gene expression profiles among experimental groups. The two-way ANOVA model is illustrated using cDNA microarrays of 3,800 genes obtained in an experiment to search for changes in gene expression profiles during neuronal differentiation of cortical stem cells.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제8권2호
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• pp.177-193
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• 2005

Purpose: To identify genes specifically expressed in biliary atresia, we compared the patterns of gene expression between biliary atresia and neonatal hepatitis syndrome using cDNA microarray analysis. Methods: Liver tissues were taken from livers of 11 patients (7 patients with biliary atresia and four with neonatal hepatitis) with neonatal cholestasis by needle biopsy. Normal control could be obtained from donor liver tissue during living-related liver transplantation. Total RNA was extracted from each samples and reversely transcribed to make cDNA. Then fluorescent cDNA were pooled and hybridized to the clones on the microarray. Fluorescence intensities at the immobilized targets were measured. Utilizing cDNA arrays of 4.7 K human genes, gene expression profiles were analyzed. Results: Among 4,700 microarray clones, 17 cDNA clones were significantly over-expressed in all 11 patients with neonatal cholestasis, while 20 clones were significantly decreased. Genome-wide expression analysis was carried out in livers obtained at the time of diagnosis. We could identify 49 genes, in which there showed differential expression between biliary atresia and neonatal hepatitis syndrome. Conclusion: This study shows the pattern of differentially expressed genes in biliary atresia and neonatal hepatitis syndrome. We believe that this study can contribute to the understanding of pathogenesis of neonatal cholestasis.

• Environmental Analysis Health and Toxicology
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• 제20권4호통권51호
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• pp.327-332
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• 2005

장기간 노출 시 발암 등 인체 유해성을 갖는 환경유래 내분비장애물질(endocrine disrupting chemicals, EDCs)에 대한 선택적이고 민감한 노출지표를 개발하기 위하여 본 연구에서는 DNA microarray를 이용하였다. 피험자는 아직 특별한 질환을 갖지 않는 18세 이상 연령, 성을 맞춘 EDCs고농도 노출군(N = 16)과 저농도군(N = 16)으로 구성되었다. 노출정도 구분은 10년 이상 거주지가 K산업폐기물 소각장과 2.5 km 반경 내, 외 인지에 따라 고노출군,저노출군으로 구분하였다. 피험자의 말초혈에서 total RNA를 분리, 각 군당 B인씩 pool로 cDNA를 합성하여 oligonucleotide DNA 칩에 적용하였다. 유전자발현의 차이를 GenePixPro 4.0 software를 이용하여 분석하였다. 총 3장의 칩을 이용하여 공통적으로 저노출군보다 고노출군에서 2배 이상 발현의 증가를 보인 유전자는 plasminogen activator(PLAT)등 12종이 관찰되었고, l/2이하로 발현의 감소를 보인 유전자는 kallikrein 3 (KLK3)등 29종이었다. 이 들 유전자는 PLAT등 면역계 반응에 관여하는 유전자 및 apoptosis, transport, G protein, chromatin, 암화, 발생 (development), 대사 등에 관여하는 유전자들이었다. 그러므로 KLK3등 본 연구에서 발굴한 유전자는 향후 확대된 인구에서 본 연구 결과의 확인을 통하여 EDCs특이적 노출지표로써, 나아가 암 등 EDCs관련 질병의 기전 및 병인학을 구명하는데 이용가치가 높다고 사료된다.