• Development and Reproduction
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• v.12 no.3
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• pp.289-296
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• 2008

BPES (Blepharophimosis/Ptosis/Epicanthus inversus Syndrome) is an autosomal dominant disorder caused by mutations in FOXL2. Affected individuals have premature ovarian failure (POF) in addition to small palpebral fissures, drooping eyelids, and broad nasal bridge. FOXL2 is a member of the forkhead family transcription factors. In FOXL2-deficient ovaries, granulosa cell differentiation dose not progress, leading to arrest of folliculogenesis and oocytes atresia. Using yeast two-hybrid screening of rat ovarian cDNA library with FOXL2 as bait, we found that small ubiquitin-related modifier (SUMO)-conjugating E2 enzyme UBE2I protein interacted with FOXL2 protein. UBE2I also known as UBC9 is an essential protein for processing SUMO modification. Sumoylation is a form of post-translational modification involved in diverse signaling pathways including the regulation of transcriptional activities of many transcriptional factors. In the present study, we confirmed the protein-protein interaction between FOXL2 and UBE2I in human cells, 293T, by in vivo immunoprecipitation. In addition, we generated truncated FOXL2 mutants and identified the region of FOXL2 required for its association with UBE2I using yeast-two hybrid system. Therefore, the identification of UBE2I as an interacting protein of FOXL2 further suggests a presence of novel regulatory mechanism of FOXL2 by sumoylation.

• Journal of Life Science
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• v.28 no.12
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• pp.1432-1437
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• 2018

Clara cell secretory protein (CCSP) plays an important role in protecting the lungs from inflammation. This research focuses on identifying the cis-element for binding the repressor of CCSP gene expression. A DNase I footprinting experiment revealed three protected regions between -812 and -768 bp (45 bp) of the mCCSP promoter. One motif (D3: GCCTGGGAA) was 100% conserved across rat, hamster, and human. The addition of excess amounts of the D3 motif exhibited high competition within that 45 bp range in an electrophoretic mobility shift assay. However, when mutated D3 ($G{\underline{AA}}TG{\underline{TT}}AA$) was used, the competition was significantly reduced. This demonstrates that the D3 motif within that 45 bp region of the mCCSP promoter is an important site for the protein-DNA interaction. Transient transfection assays with -756 Luc resulted in highly decreased expression of CCSP than those with -812 Luc, suggesting that the 45 bp could function as a binding site for the repressor. Co-transfection of KLF4 exhibited significant repression of the -812 Luc but not the -768 Luc which clearly shows that KLF4 might function as a repressor for the CCSP gene and also suggests that the D3 motif is strongly involved in the binding of KLF4. In addition, when anti-KLF4 antibody was added, super-shifted bands were observed. This result demonstrates that KLF4 could function as a repressor by binding to this 45 bp region of the CCSP promoter and that the D3 motif might be involved in the specific binding of KLF4.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1426-1436
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• 2004

There have been several reports on the relationship between G protein β3 subunit gene (GNB3), angiotensin converting enzyme gene (ACE), β3-adrenergic receptor gene (ADRB3), and β2-adrenergic receptor gene (ADRB2) genotype and obesity or obesity related disease. The objective of this study was to examine the relationship between the combinations of these four genes' polymorphism and probability of obesity related disease in Korean female subjects. The experimental group was consisted of 85 obese Korean female subjects (body mass index, BMI≥27㎏/㎡). To determine the polymorphism, genomic DNA was isolated, and PCR was performed. Serological examinations (fasting plasma glucose, FPG; aspartate aminotranferase, AST; alanine aminotransferase, ALT; total cholesterol, TC; triglyceride, TG; high density lipoprotein-cholesterol, HDL; low density lipoprotein-choles terol, LDL) were carried by an autoanalyzer and serological methods. BMI, waist circumference (WC), hip circumference and waist hip ratio (WHR) were measured. Consequencely in the analysis with grouping of general genotyping and variant allele carrier/non-carrier, the result was not significantly different within all gene combinations and polymorphic pairings except higher waist circumference in Arg16Arg group of ADRB2 codon16 (P=0.024). And there was no significantly contrast result about age, height, weight, AST and ALT that are index feature of liver and gall bladder disease in polymorphic pairings of gene combinations. However, the statistical analysis of waist-hip ratio and waist circumference that could be recognized as the physical type of obesity showed T-Arg16 pairing carrier in GNB3-ADRB2 codon16 combination had increased WHR and WC significantly (P=0.046 and P=0.015 respectively). Futhermore, the levels of total cholesterol (TC) and low density lipoprotein choresteral (LDL) were significantly lower in C-I pairing of GNB3-ACE combination (P=0.032 and P=0.005). These results suggest that the T-Arg16 pairing carrier in GNB3-ADRB2 codon16 gene might have increased waist circumference and C-I pairing carrier in GNB3-ACE combination have lower possibility of contraction of cardiovascular disease related cholesterol and LDL despite of obese state.

• Experimental and Molecular Medicine
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• v.50 no.12
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• pp.1.1-1.14
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• 2018

DNA methylation is a regulatory mechanism in epigenetics that is frequently altered during human carcinogenesis. To detect critical methylation events associated with gastric cancer (GC), we compared three DNA methylomes from gastric mucosa (GM), intestinal metaplasia (IM), and gastric tumor (GT) cells that were microscopically dissected from an intestinal-type early gastric cancer (EGC) using methylated DNA binding domain sequencing (MBD-seq) and reduced representation bisulfite sequencing (RRBS) analysis. In this study, we focused on differentially methylated promoters (DMPs) that could be directly associated with gene expression. We detected 2,761 and 677 DMPs between the GT and GM by MBD-seq and RRBS, respectively, and for a total of 3,035 DMPs. Then, 514 (17%) of all DMPs were detected in the IM genome, which is a precancer of GC, supporting that some DMPs might represent an early event in gastric carcinogenesis. A pathway analysis of all DMPs demonstrated that 59 G protein-coupled receptor (GPCR) genes linked to the hypermethylated DMPs were significantly enriched in a neuroactive ligand-receptor interaction pathway. Furthermore, among the 59 GPCRs, six GI hormone receptor genes (NPY1R, PPYR1, PTGDR, PTGER2, PTGER3, and SSTR2) that play an inhibitory role in the secretion of gastrin or gastric acid were selected and validated as potential biomarkers for the diagnosis or prognosis of GC patients in two cohorts. These data suggest that the loss of function of gastrointestinal (GI) hormone receptors by promoter methylation may lead to gastric carcinogenesis because gastrin and gastric acid have been known to play a role in cell differentiation and carcinogenesis in the GI tract.

• Molecules and Cells
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• v.20 no.1
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• pp.83-89
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• 2005

HtrA2/Omi is a mammalian mitochondrial serine protease homologous to the E. coli HtrA/DegP gene products. Recently, HtrA2/Omi was found to have a dual role in mammalian cells, acting as an apoptosis-inducing protein and being involved in maintenance of mitochondrial homeostasis. By screening a human brain cDNA library with $A{\beta}$ peptide as bait in a yeast two-hybrid system, we identified HtrA2/Omi as a binding partner of $A{\beta}$ peptide. The interaction between $A{\beta}$ peptide and HtrA2/Omi was confirmed by an immunoblot binding assay. The possible involvement of HtrA2/Omi in $A{\beta}$ peptide metabolism was investigated. In vitro peptide cleavage assays showed that HtrA2/Omi did not directly promote the production of $A{\beta}$ peptide at the ${\beta}/{\gamma}$-secretase level, or the degradation of $A{\beta}$ peptide. However, overexpression of HtrA2/Omi in K269 cells decreased the production of $A{\beta}40$ and $A{\beta}42$ by up to 30%. These results rule out the involvement of HtrA2/Omi in the etiology of Alzheimer's disease. However, the fact that overexpression of HtrA2/Omi reduces the generation of $A{\beta}40$ and $A{\beta}42$ suggests that it may play some positive role in mammalian cells.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.78.2-79
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• 2003

Pepper defensin ( CADEFl) clone was isolated from cDNA library constructed from pepper leaves infected with avirulent strain Bv5-4a of Xanthomonu campestris pv. vesicatoria. The deduced amino acid sequence of CADEFl is 82-64％ identical to that of other plant defensins. Putative protein encoded by CADEFl gene consists of 78 amino acids and 8 conserved cysteine residues to form four structure-stabilizing disulfide bridges. Transcription of the CADEF1 gene was earlier and stronger induced by X campestris pv. vesicatoria infection in the incompatible than in the compatible interaction. CADEF1 mRNA was constitutively expressed in stem, root and green fruit of pepper. Transcripts of CADEFl gene drastically accumulated in pepper leaf tissues treated With Salicylic acid (SA), methyl jasmonate (MeJA), abscisic acid (ABA), hydrogen Peroxide (H$_2$O$_2$), benzothiadiazole (BTH) and DL-${\beta}$-amino-n-butyric acid (BABA). In situ hybridization results revealed that CADEF1 mRNA was localized in the phloem areas of vascular bundles in leaf tissues treated with exogenous SA, MeJA and ABA. Strong accumulation of CADEF1 mRNA occurred in pepper leaves in response to wounding, high salinity and drought stress. These results suggest that bacterial pathogen infection, abiotic elicitors and some environmental stresses may play a significant role in signal transduction pathway for CADEF1 gene expression.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2004.10a
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• pp.65-67
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• 2004

During initial interactions of bacteria with their host plants, most plants recognize the bacterial infections and repel the pathogen by plant defense mechanism. The most active plant defense mechanism is the hypersensitive response (HR) which is the localized induced cell death in the plant at the site of infection by a pathogen. A primary locus induced in gram-negative phytopathogenic bacteria during this initial interaction is the Hrp locus. The Hrp locus is composed of a cluster of genes that encodes the bacteral Type 111 machinery that is involved in the secretion and translocation of effector proteins to the plant cell. DNA sequence analysis of hrp gene in phytopathogenic bacteria has revealed a Hrp pathogenicity is]and (PAI) with a tripartite mosaic structure. For many gram-negative pathogenic bacteria, colonization of the host's tissue depends on the type III protein secretion system (TTSS) which secrets and translocates effector proteins into the host cell. Effectors can be divided into several groups including broad host range effectors, host specific effectors, disease specific effectors, and effectors inhibit host defenses. The role of effectors carrying LRR domain in plant resistance is very elusive since most known plant resistance gene carry LRR domain. Host specific effectors such as several avr gene products are involved in the determination of the host specificity. Almost all the phytopathogenic Xanthomonas spp. carry avrBs1, avrBs2, and avrBs3 homologs. Some strains of X. oryzae pv. oryzae carry more than 10 copies of avrBs3 homologs. However, the functions of all those avr genes in host specificity are not characterized well.;

• BMB Reports
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• v.39 no.6
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• pp.709-716
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• 2006

Mammalian polo-like kinase 1 (Plk1) acts at various stages in early and late mitosis. Plk1 localizes at the centrosome and maintains this position through mitosis. Thereafter Plk1 moves to the kinetochore and midbody region, important sites during chromosome separation and cytokinesis. The catalytic domain of Plk1 is in the N-terminus region, whereas the non-catalytic region in the C-terminus of Plk1 has a conserved motif, named the Polobox. This motif is critical for Plk localization. EGFP proteins fused with the N-terminus and C-terminus of Plk1 localize in the nucleus and centrosomes, respectively. The core sequences of the polo-box (50 amino acids) also localize in Plk1 target organelles. To screen for domain-specific target proteins of Plk1, we constructed an N-terminal domain and a tandem repeat polo-box motif, and used them as templates in a yeast two-hybrid screen. The HeLa cell cDNA library indicated several proteins including the centrosome/kinetochore components or regulators, to be characterized as positive clones. Through in vitro protein binding analyses, we confirmed an interaction between these proteins and Plk1. The data reported from this study indicate that the N- and C- termini of Plk1 may function through recruitment and/or activation of domain-specific target proteins in dividing cells. Additionally, tandem repeats of the conserved core motif of the polo-box are sufficient for targeting and may be useful as a centrosome/kinetochore-specific targeting peptide.

• Genomics & Informatics
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• v.3 no.4
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• pp.142-148
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• 2005

The immune response-related genes have been suggested to be the most favorable genes for positive selection during evolution. Comparing the entire DNA sequence of chimpanzee chromosome 22 (PTR22) with human chromosome 21 (HSA21), we have identified 15 orthologs having indel in their coding sequences. Among them, interferon-${\alpha}$ receptor-1 gene (IFNAR1), an immuneresponse-related gene, is subjected to comparative genomic analysis. Chimpanzee IFNAR1 showed the same genomic structure as human IFNAR1 (11 exons and 10 introns) except the 3 bp insertion in exon 4. The sequence alignment of IFNAR1 coding sequence indicated that 'ISPP' amino acid sequence motif is highly conserved in chimpanzee and other animals including mouse and chicken. However, the human IFNAR1 shows that one proline residue is missing in the sequence motif. The homology modeling of the IFNAR1 structures suggests that the proline deletion in human IFNAR1 leads to the formation of the following ${\alpha}$-helix, whereas two sequential prolines in chimpanzee IFNAR1 inhibit it. As a result, human IFNAR1 may adopt a characteristic structure distinct from chimpanzee IFNAR1. This human specific trait could contribute to specific immune response in the most optimized manner for humans. Further molecular biological studies on the IFNAR1 will help us to gain insights into the molecular implication of species-specific host-pathogen interaction in primate evolution.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.3
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• pp.265-273
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• 2024

This study aims to explore possible effect of RNA polymerase I subunit D (POLR1D) on proliferation and angiogenesis ability of colorectal cancer (CRC) cells and mechanism herein. The correlation of POLR1D and Yin Yang 1 (YY1) expressions with prognosis of CRC patients in TCGA database was analyzed. Quantitative realtime polymerase chain reaction (qRT-PCR) and Western blot were applied to detect expression levels of POLR1D and YY1 in CRC cell lines and CRC tissues. SW480 and HT-29 cells were transfected with si-POLR1D or pcDNA3.1-POLR1D to achieve POLR1D suppression or overexpression before cell migration, angiogenesis of human umbilical vein endothelial cells were assessed. Western blot was used to detect expressions of p38 MAPK signal pathway related proteins and interaction of YY1 with POLR1D was confirmed by dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP). TCGA data showed that both POLR1D and YY1 expressions were up-regulated in CRC patients. High expression of POLR1D was associated with poor prognosis of CRC patients. The results showed that POLR1D and YY1 were highly expressed in CRC cell lines. Inhibition or overexpression of POLR1D can respectively suppress or enhance proliferation and angiogenesis of CRC cells. YY1 inhibition can suppress CRC progression and deactivate p38 MAPK signal pathway, which can be counteracted by POLR1D overexpression. JASPAR predicted YY1 can bind with POLR1D promoter, which was confirmed by dual luciferase reporter gene assay and ChIP. YY1 transcription can up-regulate POLR1D expression to activate p38 MAPK signal pathway, thus promoting proliferation and angiogenesis ability of CRC cells.