• BMB Reports
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• v.50 no.4
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• pp.194-200
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• 2017

Eukaryotic gene expression is precisely regulated at all points between transcription and translation. In this review, we focus on translational control mediated by the 3'-untranslated regions (UTRs) of mRNAs. mRNA 3'-UTRs contain cis-acting elements that function in the regulation of protein translation or mRNA decay. Each RNA binding protein that binds to these cis-acting elements regulates mRNA translation via various mechanisms targeting the mRNA cap structure, the eukaryotic initiation factor 4E (eIF4E)-eIF4G complex, ribosomes, and the poly (A) tail. We also discuss translation-mediated regulation of mRNA fate.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.283-307
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• 1987

Glycinin and $\beta$-conglycinin are the most abundant storage protein in soybean. These proteins are known to be synthesized predominantly during germination and cell expansion phase of seed development for short period, and synthesized not in other tissues. Genes encoding these storage proteins are useful system to study the mechanism of development stage and tissue specific gene expression in eukaryotes, especially plants, at the molecular level. The cDNA and genomic clones coding for glycinin have been isolated and regulation mechanism of the gene expression has been studied. Initially, development and tissue-specific expression of the glycinin gene is regulated at the level of transcription. Post-transcriptional processing is also responsible for delayed accumulation of the mRNA. Translational control of the storage protein gene has not been reported. Post-translational modification is another strategic point to regulate the expression of the gene. It is possible to identify positive and/or negative reguratory clements in vivo by producing transgenic plants agter gene manipulation. Elucidation of activation and repression mechanism of soybean storage protein genes will contribute to the understanding of the other plant and eukaryotic genes at molecular level.

• BMB Reports
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• v.50 no.11
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• pp.539-545
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• 2017

The Integrated Stress Response (ISR) refers to a signaling pathway initiated by stress-activated $eIF2{\alpha}$ kinases. Once activated, the pathway causes attenuation of global mRNA translation while also paradoxically inducing stress response gene expression. A detailed analysis of this pathway has helped us better understand how stressed cells coordinate gene expression at translational and transcriptional levels. The translational attenuation associated with this pathway has been largely attributed to the phosphorylation of the translational initiation factor $eIF2{\alpha}$. However, independent studies are now pointing to a second translational regulation step involving a downstream ISR target, 4E-BP, in the inhibition of eIF4E and specifically cap-dependent translation. The activation of 4E-BP is consistent with previous reports implicating the roles of 4E-BP resistant, Internal Ribosome Entry Site (IRES) dependent translation in ISR active cells. In this review, we provide an overview of the translation inhibition mechanisms engaged by the ISR and how they impact the translation of stress response genes.

• Proceedings of the Microbiological Society of Korea Conference
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• 1997.04a
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• pp.62.1-62.1
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• 1997

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.100-100
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• 2002

• BMB Reports
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• v.49 no.4
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• pp.199-200
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• 2016

Gene regulation in the brain is essential for long-term plasticity and memory formation. Despite this established notion, the quantitative translational map in the brain during memory formation has not been reported. To systematically probe the changes in protein synthesis during memory formation, our recent study exploited ribosome profiling using the mouse hippocampal tissues at multiple time points after a learning event. Analysis of the resulting database revealed novel types of gene regulation after learning. First, the translation of a group of genes was rapidly suppressed without change in mRNA levels. At later time points, the expression of another group of genes was downregulated through reduction in mRNA levels. This reduction was predicted to be downstream of inhibition of ESR1 (Estrogen Receptor 1) signaling. Overexpressing Nrsn1, one of the genes whose translation was suppressed, or activating ESR1 by injecting an agonist interfered with memory formation, suggesting the functional importance of these findings. Moreover, the translation of genes encoding the translational machineries was found to be suppressed, among other genes in the mouse hippocampus. Together, this unbiased approach has revealed previously unidentified characteristics of gene regulation in the brain and highlighted the importance of repressive controls.

• Animal cells and systems
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• v.13 no.4
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• pp.371-379
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• 2009

The endocannabinoid system (ECS) plays a key role in the regulation of appetite, body weight and metabolism. We undertook the present study to further clarify the regulation of the cannabinoid CB1 receptor (CB1, CNR1) in human adipose tissue in obesity. CB1 receptor mRNA expression was ~1.6-fold (p<0.004) and 1.9-fold higher (P<0.05) in subcutaneous adipocytes from obese compared to non-obese subjects in microarray and quantitative real-time PCR studies, respectively. Higher CB1 receptor mRNA expression levels in both adipose tissue (~1.2 fold, P<0.05) and adipocytes (~2 fold, P<0.01) were observed in samples from visceral compared to subcutaneous depots collected from 22 obese individuals. Immunofluorescence confocal microscopy demonstrated the presence of CB1 receptor on adipocytes and also adipose tissue macrophages. These data indicate that adipocyte CB1 receptor is up-regulated in human obesity and visceral adipose tissue and also suggest a potential role for the ECS in modulating immune/inflammation as well as fat metabolism in adipose tissue.

• Biomolecules & Therapeutics
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• v.29 no.2
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• pp.195-204
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• 2021

Cereblon (CRBN), a substrate receptor of cullin 4-RING E3 ligase (CRL4) regulates the ubiquitination and degradation of c-Jun, mediating the lipopolysaccharide-induced cellular response. However, the upstream signaling pathway that regulates this process is unknown. In this study, we describe how endoplasmic reticulum (ER) stress reversely regulates sequestosome-1 (p62)and c-Jun protein levels. Furthermore, our study reveals that expression of p62 attenuates c-Jun protein levels through the ubiquitinproteasome system. Conversely, siRNA knockdown of p62 elevates c-Jun protein levels. Immunoprecipitation and immunoblotting experiments demonstrate that p62 interacts with c-Jun and CRBN to form a ternary protein complex. Moreover, we find that CRBN knockdown completely abolishes the inhibitory effect of p62 on c-Jun. Using brefeldin A as an inducer of ER stress, we demonstrate that the p62/c-Jun axis participates in the regulation of ER stress-induced apoptosis, and that CRBN is required for this regulation. In summary, we have identified an upstream signaling pathway, which regulates p62-mediated c-Jun degradation. Our findings elucidate the underlying molecular mechanism by which p62/c-Jun axis regulates the ER stress-induced apoptosis, and provide a new molecular connection between ER stress and apoptosis.

• BMB Reports
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• v.43 no.2
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• pp.69-78
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• 2010

Asymmetric cell division is a fundamental mechanism for the generation of body axes and cell diversity during early embryogenesis in many organisms. During intrinsically asymmetric divisions, an axis of polarity is established within the cell and the division plane is oriented to ensure the differential segregation of developmental determinants to the daughter cells. Studies in the nematode Caenorhabditis elegans have contributed greatly to our understanding of the regulatory mechanisms underlying cell polarity and asymmetric division. However, much remains to be elucidated about the molecular machinery controlling the spatiotemporal distribution of key components. In this review we discuss recent findings that reveal intricate interactions between translational control and targeted proteolysis. These two mechanisms of regulation serve to carefully modulate protein levels and reinforce asymmetries, or to eliminate proteins from certain cells.

• Mycobiology
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• v.47 no.3
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• pp.346-349
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• 2019

AMP-activated protein kinase sucrose non-fermenting 1 (Snf1) is a representative regulator of energy status that maintains cellular energy homeostasis. In addition, Snf1 is involved in the mediation of environmental stress such as salt stress. Snf1 regulates metabolic enzymes such as acetyl-CoA carboxylase, indicating a possible role for Snf1 in metabolic regulation. In this article, we performed nuclear magnetic resonance (NMR) spectroscopy to profile the metabolic changes induced by Snf1 under environmental stress. According to our NMR data, we suggest that Snf1 plays a role in regulating cellular concentrations of a variety of metabolites during environmental stress responses.