• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.262.2-262
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• 1999

No Abstract, See Full Text

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.158-159
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• 2002

• The Microorganisms and Industry
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• v.14 no.1
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• pp.17-20
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• 1988

A genetic analysis of the complex Bacillus subtilis transcriptional apparatus is essential to understand the function, regulation, and interaction of the transcriptase components during growth and sporulation. This approach in Escherichia coli has uncovered fundamental mechanisms regulating gene expression Cole and Nomura, 1986; Lindahl and Zengel, 1986) and an analysis of the B. subtilis transcriptase will allow comoparison of the E.coli system to another bacterium that has evolved under different selective pressures. To this end we used antibody probes to isolate the alpha, beta, and beta' core subunit genes from a .lambda.gtill expression vector library. To address the question of function ans regulation of the minor sigma factors that confer promoter specifity on the polymerase core (Losick et al., 1986), we used the same approach to isolate the gene for the 37,000 dalton sigma factor, sigma-37.

• Biomolecules & Therapeutics
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• v.15 no.2
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• pp.78-82
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• 2007

The proto-oncogene protein DEK is a nuclear binding phosphoprotein that has been associated with various human diseases including leukemia. Histone acetylation is an important post-translational modification which plays important role in transcriptional regulation. Auto-acetylation of histone acetyltransferase PCAF results in increment of its HAT activity and facilitation of its nuclear localization. In this study, we report that DEK inhibits PCAF auto-acetylation through direct interaction. The C-terminal acidic domains of DEK are responsible for the interaction with PCAF. Using confocal microscopy, we have shown that nuclear localization of PCAF is severely inhibited by DEK. Taken together, our results suggest that DEK may be involved in various cellular signal transduction pathways accommodated by PCAF through the regulation of PCAF auto-acetylation.

• Journal of the Korean Magnetic Resonance Society
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• v.2 no.2
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• pp.152-157
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• 1998

The diversity of RNA functions ranges from storage and propagation of genetic information to enzymatic activity during RNA processing and protein synthesis. This diversity of functions requires an equally diverse arrays of structures, and, very often, the formation of functional RNA-protein complexes. Recognition of specific RNA signals by RNA-binding proteins is central to all aspects of post-transcriptional regulation of gene expression. We will describe how NMR is being used to understand at the atomic level how these important biological processes occur.

• BMB Reports
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• v.47 no.4
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• pp.227-232
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• 2014

Histone deacetylase-3 (HDAC3) is involved in cellular proliferation, apoptosis and transcriptional repression. However, the role of HDAC3 in angiogenesis remains unknown. HDAC3 negatively regulated the expression of angiogenic factors, such as VEGF and plasminogen activator inhibitor-1 (PAI-1). HDAC3 showed binding to promoter sequences of PAI-1. HDAC3 activity was necessary for the expression regulation of PAI-1 by HDAC3. VEGF decreased the expression of HDAC3, and the down-regulation of HDAC3 enhanced endothelial cell tube formation. HDAC3 negatively regulated tumor-induced angiogenic potential. We show the novel role of HDAC3 as a negative regulator of angiogenesis.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.61-68
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• 2000

Now that the complete genomes of numerous organisms have been ascertained, key problems in molecular biology include determining the functions of the genes in each organism, the relationships that exist among these genes, and the regulatory mechanisms that control their operation. These problems can be partially addressed by using machine learning methods to induce predictive models from available data. My group is applying and developing machine learning methods for several tasks that involve characterizing gene regulation. In one project, for example, we are using machine learning methods to identify transcriptional control elements such as promoters, terminators and operons. In another project, we are using learning methods to identify and characterize sets of genes that are affected by tumor promoters in mammals. Our approach to these tasks involves learning multiple models for inter-related tasks, and applying learning algorithms to rich and diverse data sources including sequence data, microarray data, and text from the scientific literature.

• Journal of Applied Biological Chemistry
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• v.42 no.2
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• pp.62-65
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• 1999

Iron regulatory proteins (IRPs) 1 and 2 bind with equally high affinity to specific RNA stem-loop sequences known as iron-responsive elements (IRE) which mediate the post-transcriptional regulation of many genes of iron metabolism. To study putative IRE-like sequences in RNA transcripts using the IRP-IRE interaction, Eight known genes from database were selected and the RNA binding activity of IRE-like sequences were compared to IRP-2. Among them, the IRE-like sequence in 3'-untranslational region (UTR) of divalent ration transporter-1 (DCT-1) shows a significant RNA binding affinity. This finding predicts that IRE consensus sequence present within 3'-UTR of DCT-1 might confer the regulation by IRP-2.

• YAKHAK HOEJI
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• v.49 no.3
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• pp.205-211
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• 2005

The 3' UTR (3' untranslated region) plays important roles in controlling gene expression through regulating 3' polyadenylation, mRNA export, subcellular localization, translational efficiency, and mRNA stability. Changes in the 3' UTR sequence in an expressed transcript can result in functional changes of the genes that are expressed in pathological conditions compared with those genes expressed in normal physiologic conditions. A genome-wide survey of 3' UTR variation was performed for the genes expressed during hematopoietic differentiation from CD34+ stem/progenitor cells to CD 15 + myeloid progenitor cells. Wide-spread differential usage of the 3' UTR was observed from the genes expressed during this cellular transition. This study implies that the 3' UTR can be a highly coordinated region for post-transcriptional regulation of the function of expressed genes.

• YAKHAK HOEJI
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• v.46 no.2
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• pp.143-148
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• 2002

The human polyomavirus JC virus is the etiologic agent of progressive multifocal leukoencephalopathy (PML). The JC virus early promoter directs cell-specific expression of the viral replication factor large T antigen, thus transcriptional regulation constitutes a major mechanism of glial tropism in PML. Here we found that pentanucleotide sequence immediately upstream of the TATA sequence functions as a cell-specific silencer in the JC virus transcription. In vitro binding studies showed that synthetic oligonucleotides spanning a pentanucleotide sequence, designated "oligo 2", interacts with nuclear proteins from non-glial cells in a cell-specific manner. Furthermore, the sequence preferentially repressed the heterologous thymidine kinase promoter activity in non-glial cells. We also tested whether JC virus transcription is controlled by DNA methylation. Transient transfection of in vitro methylated JC virus promoter abolished transcription in both the glial and non-glial cells. The repression fold was much larger in glial cells than in non-glial cells. Taken together, this finding suggests that glial cell-specific expression of the JC virus is controlled by DNA methylation as well as cell-specific silencers.