• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.47-54
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• 1998

Interleukin-10(IL-10) inhibits production of a wide range of cytokines in various cell types and transcriptionally inhibits lipopolysaccharide (LPS)-induced expression of proinflammatory mediators. Cytokine expression by macrophages is an important aspect to ochestrate inflammatory responses. As an approach to identify mechanistic targets of IL-10, it was examined the time course for expression of KC(murine homologue of Gro) gene in murine peritoneal macrophages stimulated with LPS with or without IL-10. The effect of IL-10 on LPS induced KC mRNA expression was delayed and only seen after 1 hour treatment. Pretreatment with IL-10 did not eliminate the delayed inhibitory response nor increase the magnitude of suppression. These effects did not depend upon time of IL-10 treatment but the time of LPS treatment. LPS-induced KC mRNA expression by inhibitory action of IL-10 was not controlled at the level of transcription. The result indicates that IL-10 acts late in the process of KC gene expression and that the prominant site of action may be mRNA stability or translation.

• BMB Reports
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• v.45 no.1
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• pp.26-31
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• 2012

TRIM72 is known to play a critical role in skeletal muscle membrane repair. To better understand the molecular mechanisms of this protein, we carried out an in vitro binding study with TRIM72. Our study proved that TRIM72 binds various lipids with dissociation constants ($K_d$) ranging from 88.2 ${\pm}$ 9.9 nM to 550.5 ${\pm}$ 134.5 nM. In addition, the intrinsic fluorescence of TRIM72 exponentially decreased when the protein was diluted with stirring. The time-resolved fluorescence decay occurred in a concentration-independent manner. The fluorescence-decayed TRIM72 remained in its secondary structure, but its binding properties were significantly reduced. The dissociation constants ($K_d$) of fluorescence-decayed TRIM72 for palmitate and stearate were 159.1 ${\pm}$ 39.9 nM and 355.4 ${\pm}$ 106.0 nM, respectively. This study suggests that TRIM72 can be dynamically converted by various stimuli. The results of this study also provide insight into the role of TRIM72 in the repair of sarcolemma damage.

• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.17-17
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• 2016

Calcineurin governs stress survival, sexual differentiation, and virulence of the human fungal pathogen Cryptococcus neoformans. Herein, we identified and characterized calcineurin substrates in C. neoformans by employing phosphoproteomic $TiO_2$ enrichment and quantitative mass spectrometry. The identified targets include the zinc finger transcription factor Crz1 and proteins whose functions are linked to P-bodies/stress granules (PBs/SGs) and mRNA translation and decay, such as Pbp1 and Puf4. We show that Crz1 is a bona fide calcineurin substrate, and localization and transcriptional activity of Crz1 are controlled by calcineurin. Several of the calcineurin targets localized to PBs/SGs, including Puf4 and Pbp1, and are required for survival at high temperature and for virulence. Genetic epistasis analysis revealed that Crz1 and the novel targets Lhp1, Puf4, and Pbp1 function in a branched calcineurin pathway that orchestrates stress survival and virulence. These findings propose that calcineurin controls thermal stress and virulence at the transcriptional level via Crz1 and post-transcriptionally by regulating target factors involved in mRNA metabolism.

• Reproductive and Developmental Biology
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• v.39 no.3
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• pp.59-67
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• 2015

Galactose-${\alpha}1,3$-galactose (${\alpha}1,3$-Gal) epitope is synthesized at a high concentration on the surface of pig cells by ${\alpha}1,3$-galactosyltransferase gene (GGTA1). The ${\alpha}1,3$-Gal is responsible for hyperacute rejection in pig-to-human xenotransplantation. The generation of transgenic pigs as organ donors for humans is necessary to eliminate the GGTA1 gene that synthesize $Gal{\alpha}$(1,3)Gal. To prevent hyperacute graft rejection in pig-to-human xenotransplantation, previously, we developed ${\alpha}1,3$-galactosyltransferase gene-knock-out somatic cell by homologous recombination. In this study, we established cell lines of ${\alpha}1,3$-GT knock-out expressing hDAF and hHT gene from minipig fibroblasts to apply somatic cell nuclear transfer. The hDAF and hHT mRNA were expressed in the knock-in somatic cells and ${\alpha}1,3$-GT mRNA was suppressed. However, the knock-in somatic cells were increased resistance to human serum-mediated cytolysis.

• The Korean Journal of Zoology
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• v.28 no.2
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• pp.108-119
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• 1985

Aimed at elucidating the modulation of stress protein gene expression, the effect of environmental stress and pH on the induction of stress protein synthesis has been analyzed using SDS-polyacrylamide gel electrophoresis. Although the general patterns of protein synthesis in MEF and SCK cells are different, stress protein patterns are identical in both cells. Among three stress proteins, the $SP_70$ exhibits an interesting kinetics of induction and decay. The kinetics of $SP_70$ under acidic or normal pH appears to be similar, but the degree of hyperthermia and duration of treatment required for maximum induction are found to be different, being lower temperatures and shorter durations under acidic pH compared to those under normal pH. Inducation of stress protein and the accumulation of mRNA coding for stress proteins are blocked with actinomycin D, indicating the new RNA transcription is required for stress blocked with actinomycin D, indicating that new RNA transcription is required for stress protein induction. Treatment of cycloheximide during the after hyperthermia indicates that no specific protein is required for the induction of stress protein synthesis. Based on our preliminary data, we postulate that induction of stress protein synthesis in MEF and SCK cells is regulated primarily at the level of transcription and that $SP_70$ autoregulates its synthesis and levels of this protein are correlated with the stresseed state of a cell.

• Journal of Life Science
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• v.30 no.6
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• pp.570-579
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• 2020

Pre-mRNA splicing is a crucial step for the expression of information encoded in eukaryotic genomes. Alternative splicing occurs when splice sites are differentially recognized and more than one transcript and potentially multiple proteins are generated from the same pre-mRNA. The decision on which splice sites are selected under particular cellular conditions is determined by the interaction of proteins, globally designated as splicing factors, that guide spliceosomal components, and thereby the spliceosome, to their respective splice sites. Abiotic stresses such as heat, cold, salt, drought, and hypoxia markedly alter alternative splicing patterns in plants, and these splicing events implement changes in gene expression for adaptive responses to adverse environments. Alteration of the expression or activity of splicing factors results in alternative splicing under cold, heat, salt, or drought conditions, and alternatively spliced isoforms respond distinctly in several aspects such as expression in different tissues or degradation via nonsense-mediated decay. Spliced isoforms may vary in their subcellular localization or have different biological functions under stress conditions. Despite numerous studies, functional analyses of alternative splicing have been limited to particular abiotic stresses; the molecular mechanism of alternative splicing in abiotic stress response remains uncovered which suggests that further studies are needed in this area.