• BMB Reports
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• v.49 no.2
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• pp.99-104
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• 2016

The nuclear non-histone protein high mobility group box (HMGB) 1 is known to having an inhibitory effect on the repair of DNA damaged by the antitumor drug cisplatin in vitro. To investigate the role of HMGB1 in living cells, we studied the DNA repair of cisplatin damages in mouse fibroblast cell line, NIH-3T3. We evaluated the effect of the post-synthetic acetylation and C-terminal domain of the protein by overexpression of the parental and mutant GFP fused forms of HMGB1. The results revealed that HMGB1 had also an inhibitory effect on the repair of cisplatin damaged DNA in vivo. The silencing of HMGB1 in NIH-3T3 cells increased the cellular DNA repair potential. The increased levels of repair synthesis could be "rescued" and returned to less than normal levels if the knockdown cells were transfected with plasmids encoding HMGB1 and HMGB1 K2A. In this case, the truncated form of HMGB1 also exhibited a slight inhibitory effect.

• Journal of Life Science
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• v.14 no.4
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• pp.716-725
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• 2004

Sox protein family, a transcription factor, has been found in whole animal kingdom, and contains a sequence-specific DNA binding domain called high mobility group domain (HMG). The Sox protein family based on the amino acid sequence of HMG domain was classified into 10 groups. Each group of Sox family shows significant conservation from nematode to human. The HMG domain affect to various developmental cell differentiation through binding to enhancer and regulating other transcription factors. Recently, many molecular biologists focus their research on the illustration of Sox-related disease, evolution and phylogeny. Especially, stem cell research with Sox gene family is indispensable field for understanding of their biological functions. The understanding of Sox genes may contribute to understand their role in human genetic disease and whole animal evolution.

• Applied Biological Chemistry
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• v.29 no.1
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• pp.10-15
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• 1986

A polyacrylamide gel electrophoresis technique was applied to cytokinin-protein binding assay. Binding of soybean leaf proteins to cytokinin and relative affinities of protein fractions to cytokinin were studied. The electrophoresis technique appeared to be very useful for determination of cytokinin-protein binding, for identification of protein species binding to cytokinin and for comparison of relative affinities of the proteins to cytokinin. The presence of cytokinin-binding proteins in soybean leaves was confirmed from assays with ammonium sulfate precipitation, Sephadex G-25 chromatography, paper chromatography, and electrophoresis. Three groups of cytokinin-binding proteins were identified in the soybean leaf protein extract and two of the three showed low affinity to cytokinin, however, the third one with mobility between $0.0{\sim}0.2$, probably high molecular weight protein (s), showed high affinity in the electrophoretic analysis.

• BMB Reports
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• v.46 no.11
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• pp.544-549
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• 2013

High mobility group box 1 (HMGB1) is involved in the pathogenesis of vascular diseases. Unlike activated protein C (APC), the activation of PAR-1 by thrombin is known to elicit proinflammatory responses. To determine whether the occupancy of EPCR by the Gla-domain of APC is responsible for the PAR-1-dependent antiinflammatory activity of the protease, we pretreated HUVECs with the PC zymogen and then activated PAR-1 with thrombin. It was found that thrombin downregulates the HMGB1-mediated induction of both TNF-${\alpha}$ and IL-6 and inhibits the activation of both p38 MAPK and NF-${\kappa}B$ in HUVECs pretreated with PC. Furthermore, thrombin inhibited HMGB1-mediated hyperpermeability and leukocyte adhesion/migration by inhibiting the expression of cell adhesion molecules in HUVECs if EPCR was occupied. Collectively, these results suggest the concept that thrombin can initiate proinflammatory responses in vascular endothelial cells through the activation of PAR-1 may not hold true for normal vessels expressing EPCR under in vivo conditions.

• Journal of the Korean Magnetic Resonance Society
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• v.25 no.2
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• pp.17-23
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• 2021

High mobility group protein B1 (HMGB1) is a highly conserved, non-histone, chromatin associated nuclear protein encoded by HMGB1 gene. HMGB1 proteins may be general co-factors in Hox-mediated transcriptional activation that facilitate the access of Hox proteins to specific DNA targets. It is unclear that the exact binding interface of Hoxc9DBD and HMGB1. To identify the interface and binding affinity of Hoxc9DBD and HMGB1 A-box, the paramagnetic probe, MTSL was used in NMR titration experiment. It is attached to the N-terminal end of HMGB1 A-box by reaction with thiol groups. The backbone assignment of HMGB1 A-box was achieved with 3D NMR techinques. The ¹⁵N-labeled HMGB1 A-box was titrated with MTSL-labeled Hoxc9DBD respectively. Based on the chemical shift changes we can identify the interacting residues and further map out the binding sites on the protein structure. The NMR titration result showed that the binding interface of HMGB1 A-box is around loop-1 between helix-1 and helix-2. In addition, the additional contacts were found in N- and C-terminus. The N-terminal arm region of Hoxc9DBD is the major binding region and the loop between helix1 and helix2 is the minor binding region.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1365-1370
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• 2012

The high mobility group box-1 (HMGB1) protein and NALP3 inflammasome have been identified to play important roles in inflammation and cancer pathogenesis, but the relationships between the two and cancer remain unclear. The current study investigated the relationship between HMGB1 and the NALP3 inflammasome in THP-1 macrophages. HMGB1 was found unable to activate the NALP3 inflammasome and failed to induce the release of the IL-$1{\beta}$ and IL-18 in THP-1 macrophages. HMGB1 was also found significantly enhanced the activity of ATP to induce IL-$1{\beta}$ and IL-18 by the induction of increased expression of pro-IL-$1{\beta}$ and pro-IL-18. This process was dependent on activation of RAGE, MAPK p38 and NF-${\kappa}B$ signaling pathway. These results demonstrate that HMGB1 promotes the synthesis of pro-IL-$1{\beta}$ and pro-IL-18 in THP-1 macrophages by the activation of p38 MAPK and NF-${\kappa}B$ through RAGE. HMGB1 likely plays an important role in the first step of the release of the IL-$1{\beta}$ and IL-18, preparing for other cytokines to induce excessive release of IL-$1{\beta}$ and IL-18 which promote inflammation and cancer progression.

• Reproductive and Developmental Biology
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• v.29 no.2
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• pp.63-68
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• 2005

Cloned calves derived from somatic cell nuclear transfer (SCNT) have been frequently lost by sudden death at 1 to 3 month following healthy birth. To address whether placental anomalies are responsible for the sudden death of cloned calves, we compared protein patterns of 2 placentae derived from SCNT of Korean Native calves died suddenly at two months after birth and those of 2 normal placentae obtained from AI fetuses. Placental proteins were separated using 2-Dimensional gel electrophoresis. Approximately 800 spots were detected in placental 2-D gel stained with coomassie-blue. Then, image analysis of Malanie III (Swiss Institute for Bioinformatics) was performed to detect variations in protein spots between normal and SCNT placentae. In the comparison of normal and SCNT samples, 8 spots were identified to be up-regulated proteins and 24 spots to be down-regulated proteins in SCNT placentae, among which proteins were high mobility group protein HMG1, apolipoprotein A-1 precursor, bactenecin 1, tropomyosin beta chain, $H^+-transporting$ ATPase, carbonic anhydrase II, peroxiredoxin 2, tyrosine-rich acidic matrix protein, serum albumin precursor and cathepsin D. These results suggested that the sudden death of cloned calves might be related to abnormal protein expression in placenta.

• BMB Reports
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• v.44 no.10
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• pp.680-685
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• 2011

The AT-hook motif is a small DNA-binding protein motif that has been found in the high mobility group of non-histone chromosomal proteins. The Arabidopsis genome contains 29 genes encoding the AT-hook motif DNA-binding protein (AHL). Recent studies of Arabidopsis genes (AtAHLs) have revealed that they might play diverse functional roles during plant growth and development. In this report, we mined 20 AHL genes (OsAHLs) from the rice genome database using AtAHL genes as queries and characterized their molecular features. A phylogenetic tree revealed that OsAHL proteins can be classified into 2 evolutionary clades. Tissue expression pattern analysis revealed that all of the OsAHL genes might be functionally expressed genes with 3 distinct expression patterns. Nuclear localization analysis using transgenic Arabidopsis showed that several OsAHL proteins are exclusively localized in the nucleus, indicating that they may act as architectural transcription factors to regulate expression of their target genes during plant growth and development.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.128-133
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• 1990

The chromatin of all higher eukaryotic cells contains a group of very basic low-mole-cular weight proteins, the histones. But much less is known about histones in lower eukaryotes. Our purpose was to study the histones of the genus Rhizopus. After isolation and purification of nucleoprotein the basic nucleoproteins were analyzed by gel electrophoresis, in sodium dodecyl sulfate as well as acid/urea gels and compared with calf thymus histones. Their electrophoretic mobility in polyacrylamide gel indicate that they are histone homologous, although not identical, to the H2A, H2B, H3 and H4 histones of mammals with the exception of H1. The result suggests that Rhizopus thus appears to contain histone proteins which are homologous to the histones from in higher eukaryotes. The similarity between the calf thymus histone H1 and the Rhizopus high band group remains to be discussed.

• BMB Reports
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• v.51 no.10
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• pp.508-513
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• 2018

Fibronectin fragments found in the synovial fluid of patients with osteoarthritis (OA) induce the catabolic responses in cartilage. Nuclear high-mobility group protein Box 1 (HMGB1), a damage-associated molecular pattern, is responsible for the regulation of signaling pathways related to cell death and survival in response to various stimuli. In this study, we investigated whether changes induced by 29-kDa amino-terminal fibronectin fragment (29-kDa FN-f) in HMGB1 expression influences the pathogenesis of OA via an HMGB1-modulated autophagy signaling pathway. Human articular chondrocytes were enzymatically isolated from articular cartilage. The level of mRNA was measured by quantitative real-time PCR. The expression of proteins was examined by western blot analysis, immnunofluorescence assay, and enzyme-linked immunosorbent assay. Interaction of proteins was evaluated by immunoprecipitation. The HMGB1 level was significantly lower in human OA cartilage than in normal cartilage. Although 29-kDa FN-f significantly reduced the HMGB1 expression at the mRNA and protein levels 6 h after treatment, the cytoplasmic level of HMGB1 was increased in chondrocytes treated with 29-kDa FN-f, which significantly inhibited the interaction of HMGB1 with Beclin-1, increased the interaction of Bcl-2 with Beclin-1, and decreased the levels of Beclin-1 and phosphorylated Bcl-2. In addition, the level of microtubule-associated protein 1 light chain 3-II, an autophagy marker, was down-regulated in chondrocytes treated with 29-kDa FN-f, whereas the effect was antagonized by mTOR knockdown. Furthermore, prolonged treatment with 29-kDa FN-f significantly increased the release of HMGB1 into the culture medium. These results demonstrated that 29-kDa FN-f inhibits chondrocyte autophagy by modulating the HMGB1 signaling pathway.