• BMB Reports
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• v.32 no.5
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• pp.468-473
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• 1999

Nuclear Factor 1 (NF1) proteins are a family of transcriptional factors consisting of four different types: NF1-A, -B, -C, and -X. Some NF1 transcription factors contain a heptasequence motif, SPTSPSY, which is found as a repeat sequence in the carboxy terminal domain (CTD) of the largest subunit of RNA polymerase II. A similar heptasequence, SPTSPTY, is contained in rat liver NF1-A at a position between residues 469 and 475. In order to investigate the roles of the individual amino acids of the heptasequence of rat liver NF1-A in transcriptional activation, we systematically substituted single and multiple amino acid residues with alanine residue(s) and evaluated the transcriptional activities of the mutated NF1-A. Substitution of a single amino acid reduced transcriptional activity by 10 to 30%, except for the proline residue at position 473, whose substitution with alanine did not affect transcriptional activity. However, changes of all four serine and threonine residues to alanine or of the tyrosine residue along with the serine residue at position 469 to alanine reduced the activity to almost background levels. Our results indicate that multiple serine and threonine residues, rather than a single residue, may be involved in the modulation of the transcriptional activities of the factor. Involvement of the tyrosine residue is also implicated.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.4
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• pp.299-305
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• 2001

Activation of D1-like dopamine receptors by psychostimulants, such as amphetamine, upregulates the expression of immediate early gene and opioid peptide gene in the striatum. The genomic changes are regulated by phosphorylated transcription factors via complicated intracellular events. To evaluate temporal expression of the transcription factors by dopaminergic stimulation, the D1-like dopamine agonist, amphetamine or SKF82958, was systematically delivered. As intracellular markers in response to the agonist, phosphorylated cAMP response element-binding protein (pCREB), Fos-related antigens (FRA) and FosB immunoreactivity (IR) was compared at 20 and 120 min time points in the selected areas of the striatum. Semi-quantitative immunocytochemistry showed that amphetamine (5 mg/kg, i.p.) significantly increased pCREB-IR at 20 min, sustained up to 60 min and decreased at 120 min after the infusion. Like amphetamine, the full D1 agonist, SKF82958 (0.5 mg/kg, s.c.), also increased pCREB-IR at 20 min, but not at 120 min after the infusion in the dorsal striatum (caudoputaman, CPu) and shell of ventral striatum (nucleus accumbens, NAc). In contrast, FRA- and FosB-IR induced by SKF82958 was significantly increased at 120 min, but not at 20 min after the administration. These data indicate that SKF82958 mimics induction of CREB phosphorylation by amphetamine and differentially regulates temporal induction of pCREB, and FRA and FosB expression in the striatum.

• Molecules and Cells
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• v.43 no.2
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• pp.188-197
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• 2020

Cells are designed to be sensitive to a myriad of external cues so they can fulfil their individual destiny as part of the greater whole. A number of well-characterised signalling pathways dictate the cell's response to the external environment and incoming messages. In healthy, well-ordered homeostatic systems these signals are tightly controlled and kept in balance. However, given their powerful control over cell fate, these pathways, and the transcriptional machinery they orchestrate, are frequently hijacked during the development of neoplastic disease. A prime example is the Wnt signalling pathway that can be modulated by a variety of ligands and inhibitors, ultimately exerting its effects through the β-catenin transcription factor and its downstream target genes. Here we focus on the interplay between the three-member family of RUNX transcription factors with the Wnt pathway and how together they can influence cell behaviour and contribute to cancer development. In a recurring theme with other signalling systems, the RUNX genes and the Wnt pathway appear to operate within a series of feedback loops. RUNX genes are capable of directly and indirectly regulating different elements of the Wnt pathway to either strengthen or inhibit the signal. Equally, β-catenin and its transcriptional co-factors can control RUNX gene expression and together they can collaborate to regulate a large number of third party co-target genes.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10475-10481
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• 2015

Forkhead-box (FOX) transcription factors comprise a large gene family that contains more than 50 members in man. Extensive studies have revealed that they not only have functions in control of growth and development, but also play important roles in different diseases, especially in cancer. However, biological functions for most of the members in the FOX family remain unknown. In the present study, the expression of 39 FOX genes in 48 kinds of cancer was mined from the Gene Expression Atlas database of European Bioinformatics Institute. The analysis results showed that some FOX genes demonstrate overlapping expression in various cancers, which suggests particular biological functions. The pleiotropic features of the FOX genes make them excellent candidates in efforts aimed to give medical treatment for cancers at the genetic level. The results also indicated that different FOX genes may have the synergy or antagonistics effects in the same cancers. The study provides clues for further functional analysis of FOX genes, especially for the pleiotropic biological functions and crosstalk of FOX genes in human cancers.

• Genomics & Informatics
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• v.19 no.4
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• pp.45.1-45.8
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• 2021

Brassica napus is the third most important oilseed crop in the world; however, in Korea, it is greatly affected by cold stress, limiting seed growth and production. Plants have developed specific stress responses that are generally divided into three categories: cold-stress signaling, transcriptional/post-transcriptional regulation, and stress-response mechanisms. Large numbers of functional and regulatory proteins are involved in these processes when triggered by cold stress. Here, our objective was to investigate the different genetic factors involved in the cold-stress responses of B. napus. Consequently, we treated the Korean B. napus cultivar Naehan at the 4-week stage in cold chambers under different conditions, and RNA and cDNA were obtained. An in silico analysis included 80 cold-responsive genes downloaded from the National Center for Biotechnology Information (NCBI) database. Expression levels were assessed by reverse transcription polymerase chain reaction, and 14 cold-triggered genes were identified under cold-stress conditions. The most significant genes encoded zinc-finger proteins (33.7%), followed by MYB transcription factors (7.5%). In the future, we will select genes appropriate for improving the cold tolerance of B. napus.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3677-3683
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• 2015

Abnormally expressed microRNAs (miRNAs) and genes have been found to play key roles in esophageal squamous cell carcinoma (ESCC), but little is known about the underlying mechanisms. The aim of this paper was to assess inter-relationships and the regulatory mechanisms of ESCC through a network-based approach. We built three regulatory networks: an abnormally expressed network, a related network and a global network. Unlike previous examples, containing information only on genes or miRNAs, the prime focus was on relationships. It is worth noting that abnormally expressed network emerged as a fault map of ESCC. Theoretically, ESCC might be treated and prevented by correcting the included errors. In addition, the predicted transcription factors (TFs) obtained by the P-match method also warrant further study. Our results may further guide gene therapy researchers in the study of ESCC.

• Biomolecules & Therapeutics
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• v.13 no.4
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• pp.214-219
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• 2005

Chunghyuldan (Qingxuedan in Chinese) (CHD) has been used for patients with atherosclerosis and brain ischemia in Korea. To evaluate antiischemic activity of CHD, its antiinflammatory effect in lipopolysaccharide-induced BV-2 cells was investigated. CHD potently inhibited nitric oxide (NO) production in LPS-induced BV-2 cells with an $IC_{50}$ value of 4.8${\mu}g/ml$. CHD did not only inhibit mRNA and protein expression levels of inducible NO synthase and cyclooxygenase-2 in LPS-induced BV-2 cells, but also repressed mRNA expression levels of proinflammatory cytokines IL-l$\beta$ and TNF-$\alpha$. CHD also downregulated the activation of NF-kB and AP-l transcription factors induced by LPS. These results suggest that CHD may improve inflammatory brain ischemia by the downregulation the activation of NF-kB and AP-l transcription factors.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.638-645
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• 2013

Interferon-tau (IFNT) is thought to be the conceptus protein that signals maternal recognition of pregnancy in ruminants. We and others have observed that OCT4 expression persists in the trophectoderm of ruminants; thus, both CDX2 and OCT4 coexist during the early stages of conceptus development. The aim of this study was to examine the effect of CDX2 and OCT4 on IFNT gene transcription when evaluated with other transcription factors. Human choriocarcinoma JEG-3 cells were cotransfected with an ovine IFNT (-654-bp)-luciferase reporter (-654-IFNT-Luc) construct and several transcription factor expression plasmids. Cotransfection of the reporter construct with Cdx2, Ets2 and Jun increased transcription of -654-IFNT-Luc by about 12-fold compared with transfection of the construct alone. When cells were initially transfected with Oct4 (0 h) followed by transfection with Cdx2, Ets2 and/or Jun 24 h later, the expression of -654-IFNT-Luc was reduced to control levels. OCT4 also inhibited the stimulatory activity of CDX2 alone, but not when CDX2 was combined with JUN and/or ETS2. Thus, when combined with the other transcription factors, OCT4 exhibited little inhibitory activity towards CDX2. An inhibitor of the transcriptional coactivator CREB binding protein (CREBBP), 12S E1A, reduced CDX2/ETS2/JUN stimulated -654-IFNT-Luc expression by about 40%, indicating that the formation of an appropriate transcription factor complex is required for maximum expression. In conclusion, the presence of OCT4 may initially minimize IFNT expression; however, as elongation proceeds, the increasing expression of CDX2 and formation of the transcription complex leads to greatly increased IFNT expression, resulting in pregnancy establishment in ruminants.

• Journal of Ginseng Research
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• v.47 no.5
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• pp.662-671
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• 2023

Background: 20(S)-protopanaxadiol (PPD), a ginsenoside metabolite, has prominent benefits for the central nervous system, especially in improving learning and memory. However, its transcriptional targets in brain tissue remain unknown. Methods: In this study, we first used mass spectrometry-based drug affinity responsive target stability (DARTS) to identify the potential proteins of ginsenosides and intersected them with the transcription factor library. Second, the transcription factor PURA was confirmed as a target of PPD by biolayer interferometry (BLI) and molecular docking. Next, the effect of PPD on the transcriptional levels of target genes of PURA in brain tissues was determined by qRT-PCR. Finally, bioinformatics analysis was used to analyze the potential biological features of these target proteins. Results: The results showed three overlapping transcription factors between the proteomics of DARTS and transcription factor library. BLI analysis further showed that PPD had a higher direct interaction with PURA than parent ginsenosides. Subsequently, BLI kinetic analysis, molecular docking, and mutations in key amino acids of PURA indicated that PPD specifically bound to PURA. The results of qRT-PCR showed that PPD could increase the transcription levels of PURA target genes in brain. Finally, bioinformatics analysis showed that these target proteins were involved in learning and memory function. Conclusion: The above-mentioned findings indicate that PURA is a transcription target of PPD in brain, and PPD upregulate the transcription levels of target genes related to cognitive dysfunction by binding PURA, which could provide a chemical and biological basis for the study of treating cognitive impairment by targeting PURA.

• Journal of Plant Biotechnology
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• v.48 no.3
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• pp.124-130
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• 2021

Nitrate is an important nutrient and signaling molecule in plants that modulates the expression of many genes and regulates plant growth. In this study, we cover the research status of transcription factors related to the control of gene expression by nitrate signaling in higher plants. Nitrate reductase is a key enzyme in nitrogen assimilation, as it catalyzes the nitrate-to-nitrite reduction process in plants. A variety of factors, including nitrate, light, metabolites, phytohormones, low temperature, and drought, modulate the expression levels of nitrate reductase genes and nitrate reductase activity, which is consistent with the physiological role if. Recently, several transcription factors controlling the expression of nitrate reductase genes have been identified in higher plants. NODULE-INCEPTION-Like Proteins (NLPs) are transcription factors responsible for the nitrate-inducible expression of nitrate reductase genes. Since NLPs also control the nitrate-inducible expression of genes encoding the nitrate transporter, nitrite transporter, and nitrite reductase, the expression levels of nitrate reduction pathway-associated genes are coordinately modulated by NLPs in response to nitrate. Understanding the function of nitrate in plants will be useful to create crops with low nitrogen use.