• BMB Reports
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• v.43 no.5
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• pp.355-362
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• 2010

The sterile alpha motif (SAM) is a putative protein interaction domain involved in a wide variety of biological processes. Here we report the identification and characterization of a novel gene, SAMD4B, which encodes a putative protein of 694 amino acids with a SAM domain. Northern blot and RT-PCR analysis showed that SAMD4B is widely expressed in human embryonic and adult tissues. Transcriptional activity assays show SAMD4B suppresses transcriptional activity of L8G5-luciferase. Over-expression of SAMD4B in mammalian cells inhibited the transcriptional activities of activator protein-1 (AP-1), p53 and p21, and the inhibitory effects can be relieved by siRNA. Deletion analysis indicates that the SAM domain is the main region for transcriptional suppression. The results suggest that SAMD4B is a widely expressed gene involved in AP-1-, p53- and p21-mediated transcriptional signaling activity.

• Journal of Microbiology
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• v.37 no.4
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• pp.229-233
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• 1999

The mitochondrial plasmid pMLP1 from a white-rot fungus, Pleurotus ostreatus, is a double-stranded DNA containing 381 bp terminal inverted repeat (TIR) whose 5'-ends are covalently bound by terminal proteins. The plasmid contains two major open reading frames (ORFs), encoding putative DNA and RNA polymerases, and a minor ORF encoding a small, highly basic protein. To identify the DNA binding activity that recognizes the TIR region of pMLP1, gel retardation assays were performed with mitochondrial extracts. A specific protein binding to a region between 123 and 248 nt within TIR was observed. We examined whether the gene product of mORF1 bindes to this region specifically. E. coli cell extract which contains an overproduced mORF1 protein formed a complex specific to the region between 123 and 248 nt. Inclusion of mORF1 protein in the specific complex formed between P. ostreatus mitochondrial extract and TIR was confirmed by a supershift assay using polyclonal antibodies against the mORF1 protein. Our result suggest that the product of mORF1 may function as a terminal region recognition factor (TRF), recognizing an internal region in TIR.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.186-196
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• 2023

Dyglomera^® is an aqueous ethanol extract derived from the fruit and pods of Dichrostachys glomerata. A previous study has revealed that Dyglomera regulates adipogenesis and lipolysis by modulating AMP-activated protein kinase (AMPK) phosphorylation and increased expression levels of lipolysis-related proteins in white adipose tissue of high fat diet-induced mice and 3T3-L1 adipocyte cells. To further investigate mechanisms of Dyglomera, additional studies were performed using 3T3-L1 cells. Results revealed that Dyglomera downregulated adipogenesis by inhibiting the protein kinase B/mammalian target of rapamycin signaling pathway and reconfirmed that it downregulated gene expression levels of proliferator-activated receptor (PPAR)-γ, CCAAT enhancer binding protein α, sterol-regulation element-binding protein-1c. Dyglomera also reduced adipokines such as tumor necrosis factor alpha, interleukin-1β, and interleukin 6 by regulating leptin expression. Moreover, Dyglomera promoted beige-and-brown adipocyte-related phenotypes and regulated metabolism by increasing mitochondrial number and expression levels of genes such as T-box protein 1, transmembrane protein 26, PR domain 16, and cluster of differentiation 40 as well as thermogenic factors such as uncoupling protein 1, proliferator-activated receptor-gamma co-activator-1α, Sirtuin 1, and PPARα through AMPK activation. Thus, Dyglomera not only can inhibit adipogenesis, but also can promote lipolysis and thermogenesis and regulate metabolism by affecting adipokine secretion from 3T3-L1 adipocytes.

• Molecules and Cells
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• v.24 no.3
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• pp.445-451
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• 2007

Translation initiation factor 4E (eIF4E) is a key regulator of protein synthesis. Abnormal regulation of eIF4E is closely linked to oncogenic transformation. Several regulatory mechanisms affecting eIF4E are discussed, including transcriptional regulation, phosphorylation and binding of an inhibitor protein. However it is not clear how the level of eIF4E protein is regulated under basal conditions. Here we demonstrate that Diap1 (Drosophila Inhibitor of Apoptosis Protein), a cell death inhibitor, binds directly to eIF4E and poly-ubiquitinates it via its E3 ligase activity, promoting its proteasome-dependent degradation. Expression of Diap1 caused a reduction of Cyclin D1 protein level and inhibited the growth stimulation induced by overexpression of eIF4E. Taken together, our results suggest that the level of eIF4E protein is regulated by Diap1, and that IAPs may play a role in cap-dependent translation by regulating the level of eIF4E protein.

• Journal of Nutrition and Health
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• v.25 no.3
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• pp.256-263
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• 1992

As various metabolic alterations develope in uremic patients. their diets need to be restricted, Furthermore medical complications with accompanying anorexia result in further complications and decrease in body strength. To assess the nutritional status of hemodialyzed patients we performed evaluation for dietary intake and protein catabolic rate(PCR) For 24 clinically stable male patients undergoing maintenance hemodialysis dietary intake was estimated by 3-day food record method and PCR was calculated with blood urea nitrogen at pre and post hemodialysis. The results were as follows : 1) Average daily energy and protein intake were 26.7$\pm$5.1kcal/kg of body weight. 0.95$\pm$0.19 g/kg of body weight respectively. 2) Protein catabolic rate calculated from interdialysis blood urea nitrogen levels was 1.00$\pm$0.20g/kg of body weight. Protein catabolic rate was correlated with the amount of Protein intake(r=0.44 p<0.05) 3) Relative body weight(RBW) of the subjects was smaller than that of healthy man without hemodialysis. Calorie and protein intake and protein catabolic rate were significantly different (p<0.05) between patients with lower RBW(<90% of ideal body weight) and those with normal RBW(90~110% of ideal body weight) and those with normal RBW(90~110% of iedal body weight) 4) The duration of hemodialysis did not have a significant effect on the nutritional status of the subjects.

• Journal of the Korean Magnetic Resonance Society
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• v.21 no.1
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• pp.26-30
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• 2017

Dynamic properties of proteins can present key information on protein-ligand and protein-protein interaction. Despite their usefulness, the properties of protein dynamics have not been obtained easily due to protein stability and short-term measurement. Here, it is shown that combined method for analysis of dynamical properties. It utilizes predicted order parameter and NMR relaxation data such as $T_1$, $T_2$, and heteronuclear NOE. The suggested method could be used to know the flexibility of protein roughly without precise dynamical parameters such as order parameters through model-free analysis.

• Journal of Plant Biology
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• v.36 no.1
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• pp.83-90
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• 1993

As a part of the study on the relation between exogenous polyamines and various components necessary for protein biosynthesis in the germinating maize seeds, the effects of the polyamines on protein biosynthesis and irbosome activity were investigated. The protein biosynthesis activity by S-30 containing all components necessary for protein biosynthesis was increased by exogenous polyamines, spermidine, spermine and putrescine. As the concentration of polyamine treated was increased, the optimal Mg2+ concentration of in vitro poly U-dependent protein synthesis system was gradually reduced. However, the optimal Mg2+ concentration of poly U-dependent system containing optimal polyamine was 10 mM regardless of the sort of polyamine. It could be infered that polyamines play an important part in protein biosynthesis in the higher plant, and that the role of polyamines take partially the place of Mg2+ action. The activities of ribosome and S-100 in protein biosynthesis were increased by 46.7% and 17.7% with spermidine, and by 44.1% and 16.2% with spermine, and by 29.1% and 19.3% with putrescine. It could be concluded that the increase of protein biosynthesis by polyamines in mainly owing to the ribosome activation.

• Journal of Life Science
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• v.21 no.8
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• pp.1067-1075
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• 2011

Coiled-coil domain-containing protein 98 (CCDC98) plays a role in G2/M DNA damage checkpoint pathways by recruiting breast cancer 1 (BRCA1)-A complex to the DNA-damaged sites. However, the molecular mechanism of CCDC98 on the DNA damage-induced G2/M checkpoint pathways is unclear. In this study, we identifed Wilms tumor 1-associating protein (WTAP) as a novel CCDC98-binding protein, using tandem affinity purification. We confirmed the association between CCDC98 and WTAP using in vivo and in vitro binding assays. We demonstrated that CCDC98 regulates cyclin B1 expression by affecting WTAP protein stability. Based on these results, we suggest that CCDC98 may act as a novel cell cycle regulator by regulating the expression level of cyclin B1.

• Molecules and Cells
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• v.28 no.1
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• pp.25-30
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• 2009

${\beta}$-Arrestins turn off G protein-mediated signals and initiate distinct G protein-independent signaling pathways. We previously demonstrated that angiotensin $AT_1$ receptorbound ${\beta}$-arrestin 1 is cleaved after $Phe^{388}$ upon angiotensin II stimulation. The mechanism and signaling pathway of angiotensin II-induced ${\beta}$-arrestin cleavage remain largely unknown. Here, we show that protein Tyr phosphatase activity is involved in the regulation of ${\beta}$-arrestin 1 cleavage. Tagging of green fluorescent protein (GFP) either to the N-terminus or C-terminus of ${\beta}$-arrestin 1 induced conformational changes and the cleavage of ${\beta}$-arrestin 1 without angiotensin $AT_1$ receptor activation. Orthovanadate and molybdate, inhibitors of protein Tyr phosphatase, attenuated the cleavage of C-terminal GFP-tagged ${\beta}$-arrestin 1 in vitro. The inhibitory effects of okadaic acid and pyrophosphate, which are inhibitors of protein Ser/Thr phosphatase, were less than those of protein Tyr phosphatase inhibitors. Cell-permeable pervanadate inhibited angiotensin II-induced cleavage of ${\beta}$-arrestin 1 in COS-1 cells. Our findings suggest that Tyr phosphorylation signaling is involved in the regulation of angiotensin II-induced ${\beta}$-arrestin cleavage.

• Applied Science and Convergence Technology
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• v.24 no.1
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• pp.1-8
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• 2015

Protein immobilization on a gold surface plays an important role in the usefulness of biosensors that utilize gold-coated surfaces such as surface plasmon resonance (SPR), quartz crystal microbalance (QCM), etc. For developing high performance biosensors, it is necessarily required that immobilized proteins must remain biologically active. Loss of protein activity and maintenance of its stability on transducer surfaces is directly associated with the choice of immobilization methods, affecting protein-protein interactions. During the past decade, a variety of strategies have been extensively developed for the effective immobilization of proteins in terms of the orientation, density, and stability of immobilized proteins on analytical devices operating on different principles. In this review, recent advances and novel strategies in protein immobilization technologies developed for biosensors are briefly discussed, thereby providing an useful information for the selection of appropriate immobilization approach.