• Animal cells and systems
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• 제2권2호
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• pp.287-295
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• 1998

The Saccharomyces cerevisiae MGMT gene encodes a O6-methylguanine DNA methyltransferase that protects cells from mutation or death by DNA alkylating agents. Using an in vitro transcription system, we analyzed its promoter region to find regulatory elements for transcription initiation. DNase I footprinting and a transcription assay showed that a functional TATA box, 5'-TGATATAGCA-3', is located in the region spanning from -25 to -34. We also found one upstream repressing sequence (URS), -333 to -213, by promoter deletion and competition analysis. Gel mobility shift assays and Southwestern blot analysis using URS region indicate specific complex formations. These results indicate that several cis-acting and trans-acting elements might be involved in the transcriptional regulation of the S. cerevisiae MGMT gene.

• BMB Reports
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• 제32권5호
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• pp.456-460
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• 1999

The promoter of the HSV-1 VP16 gene contains binding sites for the cellular transcription factors such as USF, CTF, and Sp1, each of which affects basal level expression of the VP16 gene. Transcription of the VP16 gene was induced by viral immediate-early proteins, ICP0 and ICP4, in a synergistic manner but repressed by ICP22. To gain further insight into the role of ICP0 in the expression of the VP16 gene during virus infection, several mutants with deletions in each of their transcriptional regulatory elements were generated. According to transient gene expression assays of these mutants using the CAT gene as a reporter, the USF and CTF binding sites were necessary for efficient induction of the promoter in the presence of transfected ICP0 or during virus infection, whereas the Sp1 binding site had little effect on ICP0-mediated VP16 expression. These results indicate that the immediate early proteins of HSV-1 regulate expression of the VP16 gene during virus infection by modulating the activities of cellular transcription factors such as USF and CTF.

• Molecules and Cells
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• 제22권2호
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• pp.163-167
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• 2006

Histone deacetylase (HDAC) activity is commonly associated with transcriptional repression. However, there is also evidence for a function in transcriptional activation. Previous studies have demonstrated a fundamental role of deacetylase activity in $IFN{\alpha}$-responsive gene transcription. In the case of type II IFN ($IFN{\gamma}$) results are controversial: some genes require HDAC activity, while transcription of others is repressed by HDAC. To investigate the effect of HDAC on transcription of an $IFN{\gamma}$-activated gene, real-time PCR was used to measure CXCL10 mRNA in Hela cells stimulated with $IFN{\gamma}$ in the presence or absence of the HDAC inhibitor TSA. Chromatin imunoprecipitation combined with real-time PCR was used to check acetylation of histone H4 and recruitment of the STAT1 complex to the ISRE locus of the CXCL10 gene. Activation of CXCL10 transcription in response to $IFN{\gamma}$ was paralleled by a decrease in histone H4 acetylation and an increase in recruitment of the STAT1 complex to the CXCL10 ISRE locus. The transcription of CXCL10 and histone H4 deacetylation were blocked by TSA, but the latter had no obvious affect on recruitment of the STAT1 complex. Our data indicate that $IFN{\gamma}$ and STAT-dependent gene transcription requires the participation of HDAC, as does the $IFN{\alpha}$-STAT pathway.

• 한국작물학회지
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• 제59권3호
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• pp.263-281
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• 2014

전사인자는 식물에서 유전자 발현을 조절하기 위해 필수적이며, 유전자의 promoter나 enhancer 부위에 결합하며, 기본 전사 조절, 전사의 향상, 발달, 세포내 신호전달, 환경에 반응, 세포 주기의 조절 등의 역할을 수행한다. 옥수수 게놈의 염기서열 분석은 전사인자의 유전자 발현 조절의 기작을 이해하는데 도움을 줄 것으로 기대된다. 과거 옥수수의 전체 게놈의 중복으로 옥수수에서 4,000개 이상의 전사인자가 코딩 될 것으로 예상된다. 본 논문에서는 옥수수의 ABI3/VP1, AP2/EREBP, ARF, ARID, AS2, AUX/IAA, BES1, bHLH, bZIP, C2C2-CO-like, C2C2-Dof, C2C2-GATA, C2C2-YABBY, C2H2, E2F/DP, FHA, GARP-ARR-B, GeBP, GRAS, HMG, HSF, MADS, MYB, MYB-related, NAC, PHD, WRKY 전사인자의 특징을 간략히 서술하고, 전사인자의 염기서열을 분석하여 sequence logo를 통하여 각각의 도메인을 표시하였다. 이러한 전사인자 및 관련된 유전자의 분자생물학적 연구는 옥수수에서 중요한 기능을 하는 유전자의 발굴 및 육종을 위한 목표 유전자의 선발에 도움을 줄 것으로 기대된다.

• Journal of Microbiology
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• 제35권3호
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• pp.228-233
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• 1997

The MTF1 gene of Saccharomyces cerevisiae encodes a 43 kDa MITOCHONDRIAL RNA polymerase specificity factor which recognizes mitochondrial promoters to initiate correct transcription. To better understand structure-function of the MTF1 gene as well as the transcription mechanism of mitochondrial RNA polymerase, two cold-sensitive alleles of the MTF1 mutation were isolated by plasmid shuffling method after PCR-based random mutagenesis of the MTF1 gene. The mutation sites were analyzed by nucleotide sequencing. These cs phenotype mtf1 mutants were respiration competent on the nonfermentible glycerol medium at the permissive temperature, but incompetent at 13.deg.C. The cs phenotype allele of the MTF1, yJH147, encoded an L146P replacement. The other cs allele, yJH148, contained K179E and K214M double replacements. Mutations in both alleles were in a region of Mtflp which is located between domains with amino acid sequence similarities to conserved regions 2 and 3 of bacterial s factors.

• Animal cells and systems
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• 제7권1호
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• pp.63-68
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• 2003

Until recently, interest in human complement receptor type I (CR1) has focused on immune complex processing, which contributed to our understanding of regulatory mechanism of complement activation. However, the promoter structure and transcriptional regulation of human CR1 gene has not been clear. To study the unique regulation of human CR1 gene expression, we assessed promoter activity of the $5^1$-flanking region of human CR1 gene using transient transfection and gel mobility shift assays. In this study we demonstrated that NF-Y binds to the inverted CCAAT element and that the functional interaction with protein(s) which bind to the GC-rich motif may be necessary for optimal transcription of human CR1 gene. We also show that sequence elements which located at-95/58 and +45/+50 are important for optimal transcription of CR1 gene.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.63-70
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• 1998

Superoxide dismutase (SOD) and catalase constitute the first coordinated unit of defense against reactive oxygen species. Here, we examined the effect of ginseng saponins on the induction of SOD and catalase gene expression. To explore this possibility, the upstream regulatory promoter region of Cu/Zn superoxide dismutase (SODI) and catalase genes were linked to the chloramphenicol acetyl-transferase (CATI structural gene and introduced into human hepatoma HepG2 cells. Total saponin and panaxatriol did not activate the transcription of SODI and catalase genes but panaxadiol increased the transcription of these genes about 2-3 fold. Among the Panaxadiol ginsenosides, the Rb2 subtraction appeared to is a major induce of SODI and catalase genes. Using the deletion analyses and mobility shift assays, we showed that the 5051 gene was greatly activated by ginsenoside Rba through transcription factor AP2 binding sites and its induction. We also examined the effect of the content ratio of panaxadiol extracted from various compartment of ginseng on the transcription of 5031 gene. Saponin extract that contains 2.6-fold more PD than PT from the fine root Increased the SODI induction about 3-fold. These results suggest that the panaxadiol fraction and its ginsenosides could induce the antioxidant enzymes, which are important for maintaining cell viability by lowering level of oxygen radical generated from intracellular metabolism.

• 농업과학연구
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• 제46권3호
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• pp.471-488
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• 2019

Random genes were screened in two transforming ways to investigate the new genes of a ladybug using the Harmonia axyridis cDNA library stock cell cloned in the LITMUS 28i vector in a previous study. Phenotypic variation was observed after injection of the synthesized double-stranded RNA through the in vitro transcription process. The cDNA library of H. axyridis was transformed into E. coli $DH5{\alpha}$ and 10B competent cells by heat shock. Analysis of the nucleotide sequences of the 42 clones with the insert DNAs revealed that 21 clones were homologous with the genes of insects, and only one clone had a gene from H. axyridis. Thirteen of the 21 insect genes were homologous with genes from coleopteran insects. Fourteen genes were selected, which were identified by the gene screening results, and were synthesized as double-stranded RNA through in vitro transcription. One microgram of the synthesized double-stranded RNA between segments T1 and T2 were injected using a syringe into each anesthetized fourth larvae which were under 2 days old. As a result, a phenotypic variation appeared in the larva injected with the two genes. While the eggs of H. axyridis injected with distilled water hatched out three days after oviposition, the eggs of H. axyridis injected with dsHma 06 did not hatch but become shrivel a week after oviposition. Most of the H. axyridis injected with dsHma 08 died and were unable to complete the pupation or eclosion during ecdysis.

• BMB Reports
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• 제42권12호
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• pp.788-793
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• 2009

TLX2 is an orphan homeodomain transcription factor whose expression is mainly associated with tissues derived from neural crest cells. Recently, we have demonstrated that PHOX2A and PHOX2B are able to enhance the neural cell-type specific expression of human TLX2 by binding distally the 5' -flanking region. In the present work, to deepen into the TLX2 transcription regulation, we have focused on the proximal 5'-flanking region of the gene, mapping the transcription start site and identifying a minimal promoter necessary and sufficient for the basal transcription in cell lines from different origin. Site-directed mutagenesis has allowed to demonstrate that the integrity of this sequence is crucial for gene expression, while electrophoretic mobility shift assays and chromatin immunoprecipitation experiments have revealed that such an activity is dependent on the binding of a PBX factor. Consistent with these findings, such a basal promoter activity has resulted to be enhanced by the previously reported PHOX2-responding sequence.

• Journal of Microbiology and Biotechnology
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• 제5권5호
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• pp.245-249
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• 1995

Expression of the adjacent but divergently transcribed glpD and glpE gene is positively regulated by cAMP-CRP. In this study, we constructed several mutants in which a CRP-binding site is placed at different distances upstream of the glpD promoter. The effect of the spacer length on transcription activation by cAMP-CRP was tested in vivo by $\beta$-galactosidase. The cAMP-CRP complex activated transcription from glpD when bound at a number of positions, all of which lay on the same face of the DNA helix, although the degree of activation varied with the length of the spacer. By contrast, the insertion of spacer length with non-integral turns of the DNA helix extremely inhibited the activation of transcription. The observed transcription activation by cAMP of the glpD promoter was influenced by the distance between the CRP binding site and the transcription start point.