• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.39-48
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• 2021

Droughts are one of the abiotic stresses that hinders the growth and productivity of crop plants. Coping with abiotic stress is necessary to understand the molecular regulatory networks that makes plants respond to adverse environmental conditions. In our experiment to find a combination that can cope with abiotic stress (respond to drought), we screened 5 stress-inducible promoters that are expressed only under stress conditions. This founded 36 cis-elements in stress-inducible promoters. With the result we designed 2 synthetic promoters (BL1, BL2) for fine-controlled regulation by assembling cis-elements from the native promoters, which are expressed only under stress caused by droughts. Analysis of the transgenic plant (BL1-GUS, BL2-GUS) showed that the synthetic promoters increased the expression of β-glucuronidase (GUS) in transgenic plants under desiccation. Also in the transient activation assay demonstrated that synthetic promoters induced the co-transformation of effector DREB1A and DREB2C. These results expect that the synthetic promoter with a combination of drought-specific elements can be used to respond to various abiotic stress and is resistant to stress without causing growth retardation.

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.89-93
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• 1998

Tomato phenylalanine ammonia-lyase 5 (tPAL5) was identified that alternate initiation sites were utilized differentially in response to environmental stimuli (Lee et al, 1992b). In this study, we tried to look into tissue -or cell- specific expression pattern of tPAL5 gene by fusing with ${\beta}-glucuronidase$ (GUS) gene in transgenic tobacco plants. In transgenic plants, root and stem extracts contained 8~12 fold higher levels of GUS activity than petiole or leaf tissue while the highest levels of induction was observed from leaf tissue by mechanical wounding (5~11 fold). In trans-sections of stems and petioles, GUS activity was restricted to phloem cells(outer region) of developing vascular bundle and mainly at apical tip region in the root tissues. The levels of GUS activity was drastically reduced (10~12 fold reduction) when the 5'-upstream region of tPAL5 gene (-1151bp from ATG codon) was deleted up to -665. The levels of GUS expression, however, raised up by 6~8 fold when deleted up to -455. Therefore, we conclude that there are positive cis-elements at the region -1151 to -1008 and at -455 to -195 while the negative cis-element is at -1008 to -455.

• Development and Reproduction
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• v.16 no.4
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• pp.379-384
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• 2012

Lhx8 (LIM homeobox 8) gene encodes a LIM homeodomain transcriptional regulator that is preferentially expressed in germ cells and critical for mammalian folliculogenesis. However, Lhx8 DNA binding sequences are not characterized yet. We aimed to identify and characterize a cis-acting sequence of germ-cell specific transcriptional factor, Lhx8. To identify Lhx8 DNA binding element, Cyclic Amplification of Sequence Target (CAST) Analysis was performed. Electrophoretic Mobility Shift Assay (EMSA) was processed for the binding specificity of Lhx8. Luciferase assay was for the transcriptional activity of Lhx8 through identified DNA binding site. We identified a putative cis-acting sequence, TGATTG as Lhx8 DNA binding element (LBE). In addition, Lhx8 binds to the LBE with high affinity and augments transcriptional activity of luciferase reporter driven by artificial promoter containing the Lhx8 binding element. These findings indicate that Lhx8 directly regulates the transcription of genes containing Lhx8 binding element in oocytes during early folliculogenesis.

• Journal of Life Science
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• v.33 no.1
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• pp.34-42
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• 2023

In a signal transduction network, from the perception of stress signals to stress-responsive gene ex- pression, binding of various transcription factors to cis-acting elements in stress-responsive promoters coordinate the adaptation of plants to abiotic stresses. Among the AP2/ERF transcription factor family genes, group VII ERF genes, such as RAP2.12, RAP2.2, RAP2.3, AtERF73/HRE1, and AtERF71/ HRE2, are known to be involved in the response to hypoxia stress in Arabidopsis. In this study, we dissected the HRE1 promoter to identify hypoxia-responsive region(s). The 1,000 bp upstream promoter region of HRE1 showed increased promoter activity in Arabidopsis protoplasts and transgenic plants under hypoxia conditions. Analysis of the promoter deletion series of HRE1, including 1,000 bp, 800 bp, 600 bp, 400 bp, 200 bp, 100 bp, and 50 bp upstream promoter regions, using firefly luciferase and GUS as reporter genes indicated that the -200 to -100 region of the HRE1 promoter is responsible for the transcriptional activation of HRE1 in response to hypoxia. In addition, we identified two putative hypoxia-responsive cis-acting elements, the ERF-binding site and DOF-binding site, in the -200 to -100 region of the HRE1 promoter, suggesting that the expression of HRE1 might be regulated via the ERF transcription factor(s) and/or DOF transcription factor(s). Collectively, our results suggest that HRE1 contains hypoxia-responsive cis-acting elements in the -200 to -100 region of its promoter.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.356-363
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• 2015

In order to study genetic engineering in trees, the characterization of genes and promoters from trees is necessary. We isolated the promoter region (867 bp) of Pagns-LTP from poplar (P. alba ${\times}$ P. glandulosa) and characterized its activity in transgenic poplar plants using a ${\beta}$-glucuronidase (GUS) reporter gene. High-level expression of the Pagns-LTP transcript was found in poplar roots, while comparatively low-level expression was found in the young leaves. Pagns-LTP mRNA was not detected in other poplar tissues. Additionally, transgenic poplar plants that contained a Pagns-LTP promoter fused to a GUS reporter gene, displayed tissue-specific GUS enzyme activity localized in root tissue. In silico analysis of the Pagns-LTP promoter sequence reveals the presence of several cis-regulatory elements responsive to phytohormones, biotic and abiotic stresses, as well as those regulating tissue-specific expression. These results demonstrate that the Pagns-LTP promoter has tissue-specific expression activity in poplar roots and leaves that may be involved in organ development and plant resistance to various stresses. Therefore, we anticipate that the Pagns-LTP promoter would be a useful tool to genetically optimize woody plants for functional genomics.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.188-188
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• 1996

In order to gain insight into the mechanism of the regulation of cytochrome P450IAl by arylhydrocarbon, the 5'-flanking region of a trout CYP450IAl 5'flanking DNA was cloned into pCAT-basic vector and it was transfected into Hepa-1 cells. 3MC treatment to hepa Ⅰ cells transfected with fish CYP450IAl-CAT construct results in mRNA increased by 2.81 fold when it was compared with that of control This increase of mRNA was decreased by concomitantly treated flavonoids such as morin. The levels of CAT mRNA that was treated with morin was 29.2-58.0% of 3MC stimulated CAT mRNA. Further investigation to find out if there are DRE, XRE or negative regulatory cis element in CYP450IA1 gene was undertaken. Results of the deletion study of 5'flanking DNA of trout P450IA indicate the existance of the negative(-1600 ～ -1300). CAT mRNA was about two-fold higher in deleted trout CYP450IAl-CAT construct transfected cells compared to the wi Id type trout CYP450IAl-CAT construct transfected cells. And The stimulatory effect of 3MC was no longer observed in col Is containing deleted CAT construct. [Supported by grants from the Korean Ministry of Education]

• Journal of Power Electronics
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• v.18 no.6
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• pp.1670-1682
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• 2018

The further improvement of submarine propulsion is associated with the modularity of accumulator-fed inverters, such as cascaded inverters (CIs). CI technology guarantees smooth output voltages with reduced switch frequencies under linear loads. However, the output voltages of CIs are distorted under rectifier loads. This distortion requires harmonic suppression technology. One such technology is the repetitive controller (RC), which is commonly applied but suffers from poor performance in propulsion systems. In this study, the FFT spectrum of a CI under rectifier load is analyzed, and the harmonic contents are uneven in magnitude. For the purpose of harmonic suppression, the control gains at each harmonic frequency should be seriously considered. A RC with a specific harmonic gain compensation (SHGC) for CIs is proposed. This method provides additional control gains at low-order harmonic frequencies, which are difficult to achieve with conventional RCs. This SHGC consists of a band-pass filter (BPF) and proportional element and is easy to implement. These features make the proposed method suitable for submarine propulsion. Experimental results verify the feasibility of the improved RC.

• Bioinformatics and Biosystems
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• v.2 no.2
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• pp.52-57
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• 2007

The computational discovery of transcription factor binding site is one of the important tools in the genetic and genomic analysis. Rough prediction of gene regulation network and finding possible co-regulated genes are typical applications of the technique. Countless motif-discovery algorithms have been proposed for the past years. However, there is no dominant algorithm yet. Each algorithm does not give enough accuracy without extensive information. In this paper, we explore the possibility of combining multiple algorithms for the one integrated result in order to improve the performance and the convenience of researchers. Moreover, we apply new high order information that is reorganized from the set of basis predictions to the final prediction.

• Genomics & Informatics
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• v.5 no.4
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• pp.174-178
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• 2007

The earliest stages of mammalian embryogenesis are governed by the activity of maternally inherited transcripts and proteins. Cytoplasmic polyadenylation of selected maternal mRNA has been reported to be a major control mechanism of delayed translation during preimplantation embryogenesis in mice. The presence of cis-elements required for cytoplasmic polyadenylation (e.g., CPE) can serve as a useful tag in the screening of maternal genes partaking in key functions in the transcriptionally dormant egg and early embryo. However, due to its relative simplicity, UA-rich sequences satisfying the canonical rule of known CPE consensus sequences are often found in the 3'-UTR of maternal transcripts that do not actually undergo cytoplasmic polyadenylation. In this study, we developed a method to confirm the validity of candidate CPE sequences in a given gene by a multiplex comparison of 3'-UTR sequences between mammalian homologs. We found that genes undergoing cytoplasmic polyadenylation tend to create a conserved block around the CPE, while CPE-like sequences in the 3'-UTR of genes lacking cytoplasmic polyadenylation do not exhibit such conservation between species. Through this cross-species comparison, we also identified an alternative CPE in the 3'-UTR of tissue-type plasminogen activator (tPA), which is more likely to serve as a functional element. We suggest that verification of CPEs based on sequence conservation can provide a convenient tool for mass screening of factors governing the earliest processes of mammalian embryogenesis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.703-707
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• 1997

DUe to the requirement of high precision and the complexity during the tool design for electron gun elements, it sometimes causes human-errors. Also, in the case of beginners, they have more trial and error than skilled engineers. To remove these problems and increase the productivity in the practice field, it need the deveiopment of CAD system for electron gun element tools. Through this study, a CAD system of electron gun element tools which is used by used by knowledge base system including expert's technology in the practics, has been developed. To developed this system, it has used C-language under HP-UNIX system and CIS customer language of the EXCESS CAD/CAM system. An application of this system will provide effective aids to the designer in this field.