• Molecules and Cells
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• v.40 no.6
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• pp.426-433
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• 2017

Ephrin-A5 has been implicated in the regulation of brain morphogenesis and axon pathfinding. In this study, we used bacterial homologous recombination to express a LacZ reporter in various ephrin-A5 BAC clones to identify elements that regulate ephrin-A5 gene expression during mesencephalon development. We found that there is mesencephalon-specific enhancer activity localized to a specific +25.0 kb to +30.5 kb genomic region in the first intron of ephrin-A5. Further comparative genomic analysis indicated that two evolutionary conserved regions, ECR1 and ECR2, were present within this 5.5 kb region. Deletion of ECR1 from the enhancer resulted in disrupted mesencephalon-specific enhancer activity in transgenic embryos. We also found a consensus binding site for basic helix-loop-helix (bHLH) transcription factors (TFs) in a highly conserved region at the 3'-end of ECR1. We further demonstrated that specific deletion of the bHLH TF binding site abrogated the mesencephalon-specific enhancer activity in transgenic embryos. Finally, both electrophoretic mobility shift assay and luciferase-based transactivation assay revealed that the transcription factor Ascl1 bound the bHLH consensus binding site in the mesencephalon-specific ephrin-A5 enhancer in vitro. Together, these results suggest that the bHLH TF binding site in ECR1 is involved in the positive regulation of ephrin-A5 gene expression during the development of the mesencephalon.

• KSBB Journal
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• v.10 no.4
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• pp.455-460
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• 1995

Specific growth rate was controlled for the repression of acetic acid formation in the fed-batch fermentation of recombinant Escherichia coli. With controlled specific growth rate, we studied the effect of the specific growth rate on cell growth, glucose consumption, acetic acid formation, and the expression of recombinant protein (${\beta}$-lactamase). High specific growth rate caused the accumulation of glucose and acetic acid, and lowered the production of recombinant protein. However, the addition of methionine recovered the gene expression by alleviating the negative effect of acetic acid at high specific growth rate.

• Journal of fish pathology
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• v.23 no.3
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• pp.273-280
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• 2010

To determine whether rock bream Oplegnathus fasciatus can be protected from rock bream iridovirus (RBIV) infection by intramuscular injection of long double-stranded RNAs (dsRNAs), we compared protective effect of virus-specific dsRNAs corresponding to major capsid protein (MCP), ORF 084, ORF 086 genes, and virus non-specific green fluorescent protein (GFP) gene. Furthermore, to determine whether the non-specific type I interferon (IFN) response was associated with protective effect, we estimated the activation of type I IFN response in fish using expression level of IFN inducible Mx gene as a marker. As a result, mortality of fish injected with dsRNAs and challenged with RBIV was delayed for a few days when comparing with PBS injected control group. However, virus-specific dsRNA injected groups exhibited no significant differences in survival period when compared to the GFP dsRNA injected group. Semi-quantitative analysis indicated that the degree of antiviral response via type I IFN response is supposedly equal among dsRNA injected fish. These results suggest that type I IFN response rather than sequence-specific RNA interference might involve in the lengthened survival period of fish injected with virus-specific dsRNAs.

• Animal cells and systems
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• v.14 no.1
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• pp.17-23
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• 2010

We isolated warm temperature acclimation-related protein 65-kDa (Wap65) cDNA from the liver of olive flounder and investigated the mRNA expression of Wap65 and HSP70 in olive flounder exposed to osmotic (17.5, 8.75, and 4 psu) and thermal stress (25 and $30^{\circ}C$). The mRNA expression of Wap65 and HSP70 was increased by thermal stress. The mRNA expression of HSP70 was also increased by osmotic stress, whereas no significant change in Wap65 expression was detected. These results indicate that Wap65 mRNA expression occurs specifically in response to increases in water temperature, but not in response to osmotic stress. Plasma cortisol levels were also increased by osmotic and thermal stress. We also utilized the stress hormone cortisol to examine whether Wap65 expression is thermal-stress-specific. Cortisol treatment increased HSP70 mRNA expression in vitro, but had no significant effect on Wap65 mRNA expression. Thus, thermal stress, but not osmotic stress, induces Wap65 expression.

• Molecules and Cells
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• v.41 no.4
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• pp.342-350
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• 2018

Flowering time is determined by florigens. These genes include, Heading date 3a (Hd3a) and Rice FT 1 (RFT1) in rice, which are specifically expressed in the vascular tissues of leaves at the floral transition stage. To study the cis-regulatory elements present in the promoter region of Hd3a, we generated transgenic plants carrying the 1.75-kb promoter fragment of Hd3a that was fused to the ${\beta}$-glucuronidase (GUS) reporter gene. Plants expressing this construct conferred a vascular cell-specific expression pattern for the reporter gene. However, GUS was expressed in leaves at all developmental stages, including the early seedling stage when Hd3a was not detected. Furthermore, the reporter was expressed in roots at all stages. This suggests that the 1.75-kb region lackings cis-elements that regulate leaf-specific expression at the appropriate developmental stages. Deletion analyses of the promoter region indicated that regulatory elements determining vascular cell-specific expression are present in the 200-bp region between -245 bp and -45 bp from the transcription initiation site. By transforming the Hd3a-GUS construct to rice cultivar 'Taichung 65' which is defective in Ehd1, we observed that Ehd1 is the major regulatory element that controls Hd3a promoter activity.

• Biomedical Science Letters
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• v.6 no.3
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• pp.171-179
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• 2000

The lengths of thick and thin filaments in the sarcomeres of most vertebrate skeletal muscles are precisely regulated and are important structural parameters in understanding muscle contraction. Nebulin is a usually large protein that spans the whole length of thin filaments in the sarcomeres of skeletal muscles. In this paper we used SDS-PAGE and immunoblot to identify nebulin isoform proteins in muscle and non-muscle tissues. We prepared embryonic chicken tissues including skeletal muscle, cardiac muscle, smooth muscle, brain, liver to compare nebulin isoform proteins. The proteins were divided into soluble and insoluble fraction. As a result, we identified tissue specific expression of various nebulin isoform proteins in muscle and non-muscle tissues of chicken. Nebulin was detected in skeletal muscle of adult chicken about 500 kDa. Nebulett was expressed in cardiac muscle of embryonic and adult chicken about 107 kDa. A giant protein with molecular mass of about 380 kDa was identified in brain of non-muscle of chicken. This giant protein was detected in the soluble fraction of chicken embryo. The unequal distribution of the nebulin isoform proteins suggests tissue specific regulation of the isoform expression and indicates a functional specialization of the encoded isoform subtypes.

• Journal of Plant Biotechnology
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• v.47 no.2
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• pp.172-178
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• 2020

Fruit-specific promoters play an important role in the improvement of traits, such as fruit quality through genetic engineering. In tomato, the development of fruit-specific promoters was previously reported, but less attention has been paid to the promoters involved in the fruit development stage. In this study, we characterized the gene expression patterns of tomato alcohol dehydrogenase 2 (SlAdh2) in various tissues of wild-type tomato (cv. Ailsa Craig). Our findings revealed that SlAdh2 expression levels were higher in the developing fruit than in the leaves, stems, and flowers. The ProSlAdh2 region, which is expressed at different stages of fruit development, was isolated from tomato genomic DNA. Following this, it was fused with a β-glucuronidase reporter gene (GUS) and introduced into wild-type tomato using Agrobacterium-mediated transformation to evaluate promoter activity in the various tissues of transgenic tomato. The ProSlAdh2:GUS promoter exhibited strong activity in the fruit and weak activity in the stems, but displayed undetectable activity in the leaves and flowers. Interestingly, the promoter was active from the appearance of the green fruit (1 cm in size) to the well-ripened stage in transgenic tomatoes, indicating its suitability for transgene expression during fruit development and ripening. Thus, our findings suggest that ProSlAdh2 may serve as a potential fruit-specific promoter for genetic-based improvement of tomato fruit quality.

• Korean Journal of Animal Reproduction
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• v.21 no.1
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• pp.1-7
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• 1997

Recently the production of transgenic animals to express foreign proteins in mammary glands has been a routine procedure. However, it still takes a considerable time and effort, and is faced with various technical challenges until the protein of interest is successfully made. Thus, a development of an a vitro model for mamm a ary-specific gene expression for recombinant genes was carried out in this study. To this end, bovine $\alpha$$_S1$ casein cDNA was inserted at the multiple cloning site of pMSG vector under the control of MMTV promoter. MCF$_7$ cells were tran sfected with pMSG $\alpha$$_S1$ CN by CaP0$_4$ precipitation. Transfectants were selected in HAT medium and induced with dexamethasone. The cells were analyzed with chicken anti-casein and FITC-labeled rabbit anti-chicken antibodies. The results showed that dexamethasone induced 30-40 fold increase in the MMTV- $\alpha$$_S1$ casein e expression. Therefore MCF$_7$ cells, which have multiple steroid receptors, along with pMSG vector can be used as an in vitro model for the study of mammary-specific gene expression.

• IMMUNE NETWORK
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• v.5 no.1
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• pp.30-35
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• 2005

Background: p38 and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) signaling are thought to have critical role in lipopolysaccharide (LPS)-induced immune response but the molecular mechanism underlying the induction of these signaling are not clear. Methods: Specific inhibitors for p38, SB203580, and for ERK, PD98059 were used. Cells were stimulated by LPS with or without specific MAPK inhibitors. Results: LPS activated inducible nitric oxide synthase (iNOS), subsequent NO productions, and pro-inflammatory cytokine gene expressions (TNF-${\alpha}$, IL-$1{\beta}$, IL-6, and IL-12). Treatment of both SB203580 and PD98059 decreased LPS-induced NO productions. Concomitant decreases in the expression of iNOS mRNA and protein were detected. SB203580 and PD98059 decreased LPS-induced gene expression of IL-$1{\beta}$ and IL-6. SB203580 increased LPS-induced expression of TNF-${\alpha}$ and IL-12, and reactive oxygen species production, but PD98059 had no effect. Conclusion: These results indicate that both p38 and ERK pathways are involved in LPS-stimulated NO synthesis, and expression of IL-$1{\beta}$ and IL-6. p38 signaling pathways are involved in LPS-induced TNF-${\alpha}$ and IL-12, and reactive oxygen species plays an important role in these signaling in macrophage.

• Development and Reproduction
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• v.2 no.2
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• pp.135-140
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• 1998

Protease Nexin-1 (PN-1) inhibits the activity of several serine proteases including thrombin, urokinase (uPA)-type plasminogen activator and trypsin. Tissue- and reproductive organ-specific mRNA levels of the PN-1 were investigated in Sprague-Dawley adult rat. PN-1 mRNA expression in rats was found in brain (forebrain, hindbrain), heart, liver, lung, ovary and oviduct. The level of PN-1 mRNA in male and female among the tissues was the highest in forebrain of the female. PN-1 expression in reproductive organs was found only in ovary and oviduct. These results suggest that PN-1 expression is dependent on the sex and may be related to folliculogenesis and early embryogenesis.