• Title/Summary/Keyword: novel protein

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Crystal structure and functional analysis of the surE protein identify a novel phosphatase family

  • Lee, Jae-Young;Kwak, Jae-Eun;Suh, Se-Won
    • Proceedings of the Korean Biophysical Society Conference
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    • 2001.06a
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    • pp.19-19
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    • 2001
  • The genome sequencing has revealed a large number of proteins of unknown or little characterized functions that have been well conserved during evolution. It remains a great challenge to decipher the molecular and physiological functions of these proteins. One example of the evolutionarily conserved protein family with little understood function is the surE family.(omitted)

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Structural Mechanism for the Cellular Redox Regulation by the Thiol Specific Antioxidant Proteins

  • Park, Hee-Jeong;Kang, Sang-Won;Rhee, Sue-Goo;Ryu, Seong-Eon
    • Proceedings of the Korean Biophysical Society Conference
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    • 1997.07a
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    • pp.15-15
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    • 1997
  • Recent studies indicate that hydrogen peroxide (H$_2$O$_2$), which is one of the reactive oxygen species involved in the oxidative stress, is an intracellular secondary messenger in the signal transduction. A novel family of thiol specific antioxidant (TSA) enzymes with a peroxidase activity shows no sequence homology to previously known antioxidant enzymes.(omitted)

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Sialic acid-binding protein from mushroom Paecilomyces japonica

  • Ryu, Chang-Soo;Kim, Ki-Don;Kim, Byung-Su;Kong, Kwang-Hoon;Kim, Ha-Hyung
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.317.1-317.1
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    • 2003
  • Carbohydrate-binding proteins have been isolated from various sources, including plants, animals, fungi, and bacteria, and they have been used extensively in the detection, localization, and isolation of glycoconjugates. Many carbohydrate-binding proteins are purified from mushrooms, however, only a few proteins with sialic acid-binding specificity have been reported. In the present study, a novel sialic acid-binding protein, designated PJA, has been purified from the mushroom Paecilomyces japonica. followed by extraction and affinity chromatography. (omitted)

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Regulation of a Novel Guanine Nucleotide Binding Protein Tissue Transglutaminase ($G{\alpha}_n$).

  • Im, Mie-Jae
    • BMB Reports
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    • v.34 no.2
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    • pp.95-101
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    • 2001
  • Tissue transglutaminase (TGII, $G{\alpha}h$) belongs to a family of enzymes which catalyze post-translational modification of proteins by forming isopeptides via $Ca^{2+}$-dependent reaction. Although TGII-mediated formation of isopeptides has been implicated to play a role in a variety of cellular processes, the physiological function of TGII remains unclear. In addition to this Tease activity, TGII is a guanosine triphosphatase (GTPase) which binds and hydrolyzes GTP It is now well recognized that the GTPase action of TGII regulates a receptor-mediated transmembrane signaling, functioning as a signal transducer of the receptor. This TGII function signifies that TGII is a new class of GTP-binding regulatory protein (G-protein) that differs from "Classical" heterotrimeric G-proteins. Regulation of enzyme is an important biological process for maintaining cell integrity. This review summarizes the recent development in regulation of TGII that may help for the better understanding of this unique enzyme. Since activation and inactivation of GTPase of TGII are similar to the heterotrimeric G-proteins, the regulation of heterotrimeric G-protein in the transmembrane signaling is also discussed.

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Sustained Protein Delivery System using Core/shell Nanoparticles

  • Oh, Keun-Sang;Koo, Hyoung-Mo;Yuk, Soon-Hong
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.180-180
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    • 2006
  • A novel preparation method for core/shell nanoparticles with protein drug-loaded lipid core was designed and characterized. The lipid core is composed of lecithin and protein drug and the polymeric shell is composed of Pluronics (poly (ethylene oxide)-poly (propylene oxide)-poly(ethylene oxide) triblock copolymer, F-127 For the application of core/shell nanoparticles as a protein drug carrier, lysozyme and Vascular Endothelial Growth Factor (VEGF) were loaded into the core/shell nanoparticles by electrostatic interaction and the drug release pattern was observed by manipulating the polymeric shell.

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Protein subcellular localization classification from multiple subsets of amino acid pair compositions

  • Tung, Thai Quang;Lim, Jong-Tae;Lee, Kwang-Hyung;Lee, Do-Heon
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2004.11a
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    • pp.101-106
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    • 2004
  • Subcellular localization is a key functional char acteristic of proteins. With the number of sequences entering databanks rapidly increasing, the importance of developing a powerful tool to identify protein subcellular location has become self-evident. In this paper, we introduce a novel method for predic ting protein subcellular locations from protein sequences. The main idea was motivated from the observation that amino acid pair composition data is redundant. By classifying from multiple feature subsets and using many kinds of amino acid pair composition s, we forced the classifiers to make uncorrelated errors. Therefore when we combined the predictors using a voting scheme, the prediction accuracy c ould be improved. Experiment was conducted on several data sets and significant improvement has been achieve d in a jackknife test.

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Cell cycle regulatory element in the promoter of the human thymidine kinase gene and its binding to factors

  • Kim, Yong-Kyu
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1995.10a
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    • pp.9-15
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    • 1995
  • When quiescent cells ate stimulated to enter the cell cycle, the thymidine kinase(TK) gene is transcriptionally activated at the border of Gl and 5. In this report we show that the human TK promoter contains multiple protein-binding sites. By site-directed mutagenesis, we identified a protein-binding site on the human TK promoter requited for conferring Gl-S-regulated transcription to a heterologous promoter and dissociated it functionally from an adjacent protein-binding domain containing an inverted CCAAT motif requited for high basal level expression. Substitution-mutation of this site results in constitutive expression of the neo reporter gene in serum-stimulated fibroblasts, as well as in cells arrested in mid-Gl by a temperature-sensitive mutation. The regulatory domains for the human TK promoter exhibit interesting symmetrical features, including a set of CCAAT motifs and sites similar to the novel Yi protein-binding site recently discovered in the mouse TK promoter. Thus, components of the hTK complex is important for hTK gene regulation.

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Precise assembly and regulation of 26S proteasome and correlation between proteasome dysfunction and neurodegenerative diseases

  • Im, Eunju;Chung, Kwang Chul
    • BMB Reports
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    • v.49 no.9
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    • pp.459-473
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    • 2016
  • Neurodegenerative diseases (NDs) often involve the formation of abnormal and toxic protein aggregates, which are thought to be the primary factor in ND occurrence and progression. Aged neurons exhibit marked increases in aggregated protein levels, which can lead to increased cell death in specific brain regions. As no specific drugs/therapies for treating the symptoms or/and progression of NDs are available, obtaining a complete understanding of the mechanism underlying the formation of protein aggregates is needed for designing a novel and efficient removal strategy. Intracellular proteolysis generally involves either the lysosomal or ubiquitin-proteasome system. In this review, we focus on the structure and assembly of the proteasome, proteasome-mediated protein degradation, and the multiple dynamic regulatory mechanisms governing proteasome activity. We also discuss the plausibility of the correlation between changes in proteasome activity and the occurrence of NDs.