• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2000년도 International Symposium on Bioinformatics
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• pp.56-58
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• 2000

Post-genomics may be defined in different ways depending on how one views the challenges after the genome. A popular view is to follow the concept of the central dogma in molecular biology, namely from genome to transcriptome to proteome. Projects are going on to analyze gene expression profiles both at the mRNA and protein levels and to catalog protein 3D structure families, which will no doubt help the understanding of information in the genome. However complete, such catalogs of genes, RNAs, and proteins only tell us about the building blocks of life. They do not tell us much about the wiring (interaction) of building blocks, which is essential for uncovering systemic functional behaviors of the cell or the organism. Thus, an alternative view of post-genomics is to go up from the molecular level to the cellular level, and to understand, what I call, the "interactome"or a complete picture of molecular interactions in the cell. KEGG (http://www.genome.ad.jp/kegg/) is our attempt to computerize current knowledge on various cellular processes as a collection of "generalized"protein-protein interaction networks, to develop new graph-based algorithms for predicting such networks from the genome information, and to actually reconstruct the interactomes for all the completely sequenced genomes and some partial genomes. During the reconstruction process, it becomes readily apparent that certain pathways and molecular complexes are present or absent in each organism, indicating modular structures of the interactome. In addition, the reconstruction uncovers missing components in an otherwise complete pathway or complex, which may result from misannotation of the genome or misrepresentation of the KEGG pathway. When combined with additional experimental data on protein-protein interactions, such as by yeast two-hybrid systems, the reconstruction possibly uncovers unknown partners for a particular pathway or complex. Thus, the reconstruction is tightly coupled with the annotation of individual genes, which is maintained in the GENES database in KEGG. We are also trying to expand our literature surrey to include in the GENES database most up-to-date information about gene functions.

• Asian Pacific Journal of Cancer Prevention
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• 제15권24호
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• pp.10847-10853
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• 2015

Background: Lapatinib, a dual tyrosine kinase inhibitor that interrupts the epidermal growth factor receptor (EGFR) and HER2/neu pathways, has been indicated to have significant efficacy in treating HER2-positive breast cancer. However, acquired drug resistance has become a very serious clinical problem that hampers the use of this agent. In this study, we aimed to screen small molecule drugs that might reverse lapatinib-resistance of breast cancer by exploring differentially expressed genes (DEGs) via a bioinformatics method. Materials and Methods: We downloaded the gene expression profile of BT474-J4 (acquired lapatinib-resistant) and BT474 (lapatinib-sensitive) cell lines from the Gene Expression Omnibus (GEO) database and selected differentially expressed genes (DEGs) using dChip software. Then, gene ontology and pathway enrichment analyses were performed with the DAVID database. Finally, a connectivity map was utilized for predicting potential chemicals that reverse lapatinib-resistance. Results: A total of 1, 657 DEGs were obtained. These DEGs were enriched in 10 pathways, including cell cycling, regulation of actin cytoskeleton and focal adhesion associate examples. In addition, several small molecules were screened as the potential therapeutic agents capable of overcoming lapatinib-resistance. Conclusions: The results of our analysis provided a novel strategy for investigating the mechanism of lapatinib-resistance and identifying potential small molecule drugs for breast cancer treatment.

• 동의생리병리학회지
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• 제38권1호
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• pp.22-26
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• 2024

The purpose of this study was to identify the applicability, main compounds, and target genes of Cnidii Fructus (CF) in the treatment of gastritis using network pharmacology. The compounds in CF were searched in Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and a database of medicinal materials and chemical compounds in Northeast Asian traditional medicine (TM-MC). The target gene information of the compounds was collected from pubchem and cross-compared with the gastritis-related target gene information collected from Genecard to derive the target genes. Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on the derived target genes. Afterwards, network analysis between compounds and disease target genes was performed using cytoscape. We identified 121 active compounds and 139 target genes associated with gastritis. Pathways derived from the GO biological process and KEGG pathway DB primarily focus on target genes related to inflammation (IL-6, IL-8, TNF production, NF-κB transcription factor activity, and NF-κB signaling pathway) and cell death (PI3K-Akt, FoxO). Major targets for CF treatment of gastritis include TP53, TNF, BCL2, EGFR, NFKB1, ABCB1, PPARG, PTGS2, IL6, IL1B, and SOD1, along with major compounds such as coumarin, osthol, hexadecanoic acid, oleic acid, linoleic acid, and stigmasterol. This study provided CF's applicability for gastritis, related compounds, and target information. Evaluating CF's effectiveness in a preclinical gastritis model suggests its potential use in clinical practice for digestive system diseases.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1684-1690
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• 2005

Using mRNA differential display technique, we investigated differential gene expression in hybrids relative to their parents in a diallel cross involving four chicken breeds in order to provide an insight into the molecular basis of heterosis in chicken. The results indicated that there was extensive differential gene expression between chicken F1 hybrids and their parents which was classified into four kinds of patterns as following: (1) bands only detected in hybrid F1; (2) bands only absent in hybrid F1; (3) bands only detected in parent P1 or P2; (4) bands absent in parent P1 or P2. Forty-two differentially expressed cDNAs were cloned and sequenced, and their expression patterns were confirmed by Reverse-Northern dot blot. Sequence analysis and database searches revealed that genes showed differential expression between hybrid and parents were regulatory and functional genes involved in metabolism, mRNA splicing, transcriptional regulation, cell cycles and protein modification. These results indicated that hybridization between two parents can cause changes in expression of a variety of genes. In conclusion, that the altered pattern of gene expression in hybrids may be responsible for heterosis in chickens.

• Journal of Life Science
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• 제11권1호
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• pp.52-56
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• 2001

The present study intends to characterize the DNA damage-inducible responses in eukaryotic cells. The fission yeast, S. pombe, which displays efficient DNA repair systems, was used in this study as a model system for higher eukaryotes. To study UV-inducible responses in S. pombe, five UV-inducible cDNA clones were isolated from S. pombe by using subtration hybridization method. To investigate the expression of isolated genes, the cellular levels of the transcripts of these genes were determined by Northern blot analysis after UV-irradiation. The transcripts of isolated gene (UV130) increased rapidly and reached maximum accumulation after UV-irradiation. Compared to the message levels of control, the levels of maximal increase were approximately 5 fold to UV-irradiation. In order to investigation whether the increase of UV130 transcripts was a specific results of UV-irradiation, UV130 transcript levels were examined after treating the cells to Methylmethane sulfonate (MMS). The transcripts of UV130 were not induced by treatment of 0.25% MMS. These results implied that the effects of damaging agents are complex and different regulatory pathways exist for the induction of these genes. To characterize the structure of UV130 gene, nucleotide sequences were analyzed. The nucleotide sequence of 1,340 nucleotide excluding poly(A) tail contains one open reading frame, which encodes a protein of 270 amino acids. The predicted amino acid sequences of UV130 do not exhibit any significant similarity to ther known sequences in the database.

• Molecular & Cellular Toxicology
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• 제1권1호
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• pp.52-61
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• 2005

Transcript profiling is a particularly valuable tool in the field of steroid receptor biology, as these receptors are ligand-activated transcription factors and therefore exert their initial effects through altering gene expression in responsive cells. Also, an awareness of endocrine disrupting chemicals (EDCs) and their potential screening methods to identify endocrine activity have been increased. Here we developed an in-house cDNA microarray, named KISTCHIP-400 ver. 1.0, with 416 clones, based on public database and research papers. These clones contained estrogen, androgen, thyroid hormone & receptors, sex hormone signal transduction & regulation, c-fos, c-myc, ps2 gene, metabolism related genes etc. Also, to validate the KISTCHIP-400 ver. 1.0, we investigated gene expression profiles with reference hormones, $10^{8}\;M\;17{\beta}-estradiol,\;10^{-7}\;M\;testosterone\;and\;10^{-7}\;M$ progesterone in MCF-7 cell line. As the results, gene expression profiles of three reference hormones were distinguished from each other with significant and identified 33 $17{\beta}-estradiol$ responsive genes. This study is in first step of validation for KISTCHIP-400 ver. 1.0, as following step transcriptional profile analysis on not only low concentrations of EDCs but suspected EDCs using KISTCHIP-400 ver. 1.0 is processing. Our results indicate that the developed microarray may be a useful laboratory tool for screening EDCs and elucidating endocrine disrupting mechanism.

• BMB Reports
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• 제29권1호
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• pp.45-51
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• 1996

Most expressed HLA loci exhibit a remarkable degree of allelic polymorphism, which derives from sequence differences predominantly localized to discrete hypervariable regions of the amino-terminal domain of the molecule. In this study, the HLA-DRB1 genotypes were determined in eighteen control cell lines and 112 unrelated Koreans using the PCR-SSP (Polymerase Chain Reaction-Sequence Specific Primer) technique. 29 specific primer pairs in assigning the DRB1 gene were used. The results of control cells correlated well with the data which was previously reported. The heterozygosity and homozygosity of the DRB1 gene were 0.786 and 0.214, respectively. In a total of 41 different DRB1 alleles and 83 genotypes, the most frequent allele and genotype were DRB1*04 and DRB1*0901/1501, respectively. This study shows that the PCR-SSP technique is relatively simple, fast and a practical tool for the determination of the HLA-DRBI genotypes. Moreover, these results-allele and genotype frequency and heterozygosity of the HLA DRB1 gene-could be useful for database study before being applied to individual identification and transplantation immunity.

• BMB Reports
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• 제49권4호
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• pp.199-200
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• 2016

Gene regulation in the brain is essential for long-term plasticity and memory formation. Despite this established notion, the quantitative translational map in the brain during memory formation has not been reported. To systematically probe the changes in protein synthesis during memory formation, our recent study exploited ribosome profiling using the mouse hippocampal tissues at multiple time points after a learning event. Analysis of the resulting database revealed novel types of gene regulation after learning. First, the translation of a group of genes was rapidly suppressed without change in mRNA levels. At later time points, the expression of another group of genes was downregulated through reduction in mRNA levels. This reduction was predicted to be downstream of inhibition of ESR1 (Estrogen Receptor 1) signaling. Overexpressing Nrsn1, one of the genes whose translation was suppressed, or activating ESR1 by injecting an agonist interfered with memory formation, suggesting the functional importance of these findings. Moreover, the translation of genes encoding the translational machineries was found to be suppressed, among other genes in the mouse hippocampus. Together, this unbiased approach has revealed previously unidentified characteristics of gene regulation in the brain and highlighted the importance of repressive controls.

• 한국축산시설환경학회지
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• 제21권3호
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• pp.93-98
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• 2015

The objective of this study was to review application of next-generation sequencing (NGS) to investigate microbiome in the livestock sector. Since the 16S rRNA gene is used as a phylogenetic marker, unculturable members of microbiome in nature or managed environments have been investigated using the NGS technique based on 16S rRNA genes. However, few NGS studies have been conducted to investigate microbiome in the livestock sector. The 16S rRNA gene sequences obtained from NGS are classified to microbial taxa against the 16S rRNA gene reference database such as RDP, Greengenes and Silva databases. The sequences also are clustered into species-level OTUs at 97% sequence similarity. Microbiome similarity among treatment groups is visualized using principal coordinates analysis, while microbiome shared among treatment groups is visualized using a venn diagram. The use of the NGS technique will contribute to elucidating roles of microbiome in the livestock sector.

• BMB Reports
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• 제37권2호
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• pp.148-152
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• 2004

A new molecular-baiting method was studied by retrieving targeted gene fragments from an oligonucleotide microarray bait after hybridization. To make the microarray bait, 70-mer oligonucleotides that were designed to specifically represent the SSA1 gene of Saccharomyces cerevisiae were printed on the slide. Samples of the Saccharomyces cerevisiae mRNA were extracted and labeled by the RD-PCR (Restriction Display PCR) method using the Cy5-labelled universal primer, then applied for hybridization. The sample fragments that hybridized to the microarray were stripped, and the eluted cDNAs were retrieved and cloned into the pMD 18-T vector for transformation, plasmid preparation, and sequencing. BLAST searching of the GenBank database identified the retrieved fragments as being identical to the SSA1 gene (from 2057-2541bp). A new method is being established that can retrieve the sample fragments using an oligo-microarray-bait.