• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.966-966
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• 2005

• Journal of the Korean Magnetic Resonance Society
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• v.16 no.1
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• pp.67-77
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• 2012

The small molecule binding to the c-Jun N-terminal kinase 3 (JNK3) was examined by the measurements of saturation transfer difference (STD) NMR experiments. The STD NMR experiment of ATP added to JNK3 clearly showed the binding of the nucleotide to the kinase. The STD NMR spectrum of dNTPs added to JNK3 discriminated the kinase-bound nucleotide from the unbound ones. After the five-fold addition of ATP to the dNTPs and JNK3 mixture, only signals of the cognate substrate of JNK3, ATP, were observed from the STD NMR experiment. These results signify that by the STD NMR the small molecules bound to JNK3 can be discriminated from the pool of the unbound molecules. Furthermore the binding mode of the small molecule to JNK3 can be determined by the competition experiments with ATP.

• International journal of thyroidology
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• v.11 no.2
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• pp.82-87
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• 2018

Skin-related toxicity is one of the most important adverse events from multi-target tyrosine kinase inhibitor (MTKI) to treat radioiodine refractory thyroid cancer. As hand foot skin reaction can limit quality of life and therapeutic effectiveness, it is essential to cope with a variety of severity of skin-related toxicity induced by MTKI. Herein, we will discuss two representative cases of skin-related toxicities which were managed by discontinuation/reduction of therapeutic doses of MTKI and were treated by proper medication in thyroid cancer patients with distant metastasis.

• Molecules and Cells
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• v.19 no.1
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• pp.60-66
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• 2005

Low density lipoproteins (LDL) play important roles in the pathogenesis of atherosclerosis. Diabetes is associated with accelerated atherosclerosis leading to cardiovascular disease in diabetic patients. Although LDL stimulates the proliferation of arterial smooth muscle cells (SMC), the mechanisms are not fully understood. We examined the effects of native LDL and glycated LDL on the extracellular signal-regulated kinase (ERK) pathway. Addition of native and glycated LDL to rat aorta SMCs (RASMCs) stimulated ERK phosphorylation. ERK phosphorylation was not affected by exposure to the $Ca^{2+}$ chelator BAPTA-AM but inhibition of protein kinase C (PKC) with GF109203X, inhibition of Src kinase with PP1 ($5{\mu}M$) and inhibition of phospholipase C (PLC) with U73122/U73343 ($5{\mu}M$) all reduced ERK phosphorylation in response to glycated LDL. In addition, pretreatment of the RASMCs with a cell-permeable mitogen-activated protein kinase kinase (MEK) inhibitor (PD98059, $5{\mu}M$) markedly decreased ERK phosphorylation in response to native and glycated LDL. These findings indicate that ERK phosphorylation in response to glycated LDL involves the activation of PKC, PLC, and MEK, but is independent of intracellular $Ca^{2+}$.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1712-1716
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• 2007

To generate new scaffold candidates as highly selective and potent cyelin-dependent kinase (CDK) inhibitors, structure-based drug screening was performed utilizing 3D pharmacophore conformations of known potent inhibitors. As a result, CR229 (6-bromo-2,3,4,9-tetrahydro-carbolin-1-one) was generated as the hit-compound. A computational docking study using the X-ray crystallographic structure of CDK2 in complex with CR229 was evaluated. This predicted binding mode study of CR229 with CDK2 demonstrated that CR229 interacted effectively with the Leu83 and Glu81 residues in the ATP-binding pocket of CDK2 for the possible hydrogen bond formation. Furthermore, biochemical studies on inhibitory effects of CR229 on various kinases in the human cervical cancer HeLa cells demonstrated that CR229 was a potent inhibitor of CDK2 ($IC_{50}:\;3\;{\mu}M$), CDKI ($IC_{50}:\;4.9\;{\mu}M$), and CDK4 ($IC_{50}:\;3\;{\mu}M$), yet had much less inhibitory effect ($IC_{50}:>20\;{\mu}M$) on other kinases, such as casein kinase 2-${\alpha}1$ (CK2-${\alpha}1$), protein kinase A (PKA), and protein kinase C (PKC). Accordingly, these data demonstrate that CR229 is a potent CDK inhibitor with anticancer efficacy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.984-991
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• 1997

New tumor suppressor gene, snm23, homologous to human nm23/NDP kinase (human nucleoside diphosphate kinase) gene whose product has a tumor metastasis inhibitory activity, was first cloned from Korean tiger shark (Scyliorhinus forazame) skin cDNA library constructed by using a $\lambda$ ZAP-II cDNA synthesis kit. About $1\times10^5$ plaques were screened and several positive plaques were isolated and confirmed by second screening. The phagemid containing a positive clone from the Uni-Zap XR vector was excised in vivo and the gene containing the tumor metastasis suppressor protein was named as snm23. Cloned gene, snm23, was sequenced with ABI-PRISM 310 Genetic Analyzer. The nucleotide and deduced amino acid sequences of snm23 have shown an open reading frame consisting of 450 base pairs that correspond to a protein of 150 amino acid residues, with a calculated molecular mass of 16.8 kDa. Sequence comparison of snm23 with human nm23/NDP kinase was performed by using Blast protein data base of National Center for Biotechnology Information. In order to determine tissue specificity, reverse transcription-polymerase chain reaction (RT-PCR) was used. Good expression level of snm23/NDP kinase was detected at the tissues from skin, cartilage, and liver of Korean tiger shark.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.1
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• pp.25-36
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• 2022

To identify the effect and mechanism of carbon monoxide (CO) on delayed rectifier K⁺ currents (I_K) of human cardiac fibroblasts (HCFs), we used the wholecell mode patch-clamp technique. Application of CO delivered by carbon monoxidereleasing molecule-3 (CORM3) increased the amplitude of outward K⁺ currents, and diphenyl phosphine oxide-1 (a specific I_K blocker) inhibited the currents. CORM3-induced augmentation was blocked by pretreatment with nitric oxide synthase blockers (L-NG-monomethyl arginine citrate and L-NG-nitro arginine methyl ester). Pretreatment with KT5823 (a protein kinas G blocker), 1H-[1,-2,-4] oxadiazolo-[4,-3-a] quinoxalin-1-on (ODQ, a soluble guanylate cyclase blocker), KT5720 (a protein kinase A blocker), and SQ22536 (an adenylate cyclase blocker) blocked the CORM3 stimulating effect on I_K. In addition, pretreatment with SB239063 (a p38 mitogen-activated protein kinase [MAPK] blocker) and PD98059 (a p44/42 MAPK blocker) also blocked the CORM3's effect on the currents. When testing the involvement of S-nitrosylation, pretreatment of N-ethylmaleimide (a thiol-alkylating reagent) blocked CO-induced I_K activation and DL-dithiothreitol (a reducing agent) reversed this effect. Pretreatment with 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)-21H,23H porphyrin manganese (III) pentachloride and manganese (III) tetrakis (4-benzoic acid) porphyrin chloride (superoxide dismutase mimetics), diphenyleneiodonium chloride (an NADPH oxidase blocker), or allopurinol (a xanthine oxidase blocker) also inhibited CO-induced I_K activation. These results suggest that CO enhances I_K in HCFs through the nitric oxide, phosphorylation by protein kinase G, protein kinase A, and MAPK, S-nitrosylation and reduction/oxidation (redox) signaling pathways.

• Mycobiology
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• v.51 no.5
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• pp.372-378
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• 2023

Lkh1, a LAMMER kinase homolog in the fission yeast Schizosaccharomyces pombe, acts as a negative regulator of filamentous growth and flocculation. It is also involved in the response to oxidative stress. The lkh1-deletion mutant displays slower cell growth, shorter cell size, and abnormal DNA content compared to the wild type. These phenotypes suggest that Lkh1 controls cell size and cell cycle progression. When we performed microarray analysis using the lkh1-deletion mutant, we found that only four of the up-regulated genes in the lkh1-deletion were associated with the cell cycle. Interestingly, all of these genes are regulated by the Mlu1 cell cycle box binding factor (MBF), which is a transcription complex responsible for regulating the expression of cell cycle genes during the G1/S phase. Transcription analyses of the MBF-dependent cell-cycle genes, including negative feedback regulators, confirmed the up-regulation of these genes by the deletion of lkh1. Pull-down assay confirmed the interaction between Lkh1 and Yox1, which is a negative feedback regulator of MBF. This result supports the involvement of LAMMER kinase in cell cycle regulation by modulating MBF activity. In vitro kinase assay and NetPhosK 2.0 analysis with the Yox1T40,41A mutant allele revealed that T40 and T41 residues are the phosphorylation sites mediated by Lkh1. These sites affect the G1/S cell cycle progression of fission yeast by modulating the activity of the MBF complex.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1177-1182
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• 2012

Protein kinase C (PKC) has been implicated in carcinogenesis and displays variable expression profiles during cancer progression. Studies of dietary phytochemicals on cancer signalling pathway regulation have been conducted to search for potent signalling regulatory agents. The present study was designed to evaluate any suppressive effect of maslinic acid on PKC expression in human B-lymphoblastoid cells (Raji cells), and to identify the PKC isoforms expressed. Effects of maslinic acid on PKC activity were determined using a PepTag$^{(R)}$ assay for non-radioactive detection of PKC. The highest expression in Raji cells was obtained at 20 nM PMA induced for 6 hours. Suppressive effects of maslinic acid were compared with those of four PKC inhibitors (H-7, rottlerin, sphingosine, staurosporine) and two triterpenes (oleanolic acid and ursolic acid). The $IC_{50}$ values achieved for maslinic acid, staurosporine, H-7, sphingosine, rottlerin, ursolic acid and oleanolic acid were 11.52, 0.011, 0.767, 2.45, 5.46, 27.93 and $39.29\;{\mu}M$, respectively. Four PKC isoforms, PKC ${\beta}I$, ${\beta}II$, ${\delta}$, and ${\zeta}$, were identified in Raji cells via western blotting. Maslinic acid suppressed the expression of PKC ${\beta}I$, ${\delta}$, and ${\zeta}$ in a concentration-dependent manner. These preliminary results suggest promising suppressive effects of maslinic acid on PKC activity in Raji cells. Maslinic acid could be a potent cancer chemopreventive agent that may be involved in regulating many downstream signalling pathways that are activated through PKC receptors.

• Journal of Life Science
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• v.26 no.10
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• pp.1182-1188
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• 2016

Membrane-associated guanylate kinase inverted-3 (MAGI-3) is a member of the family of membrane-associated guanylate kinases (MAGUKs). MAGI-3 modulates the kinase activity of protein kinase B (PKB)/AKT through interactions with phosphatase and tensin homolog (PTEN)/MMAC. Coxsackievirus B3 (CVB3) is a common causative agent of acute myocarditis and chronic dilated cardiomyopathy. Activation of AKT and extracellular signal-regulated kinases 1/2 (ERK1/2) is essential for CVB3 replication, but the relation between MAGI-3 signaling and CVB3 replication is not well understood. This study investigated the role of MAGI-3 in CVB3 infection and replication. MAGI-3 was overexpressed in HeLa cells by polyethylenimine (PEI) transfection. To optimize the transfection conditions, different ratios of plasmid DNA to PEI concentrations were used. MAGI-3 and empty plasmid DNA were transfected into the HeLa cells. MAGI-3 overexpression alone was not sufficient to efficiently activate AKT. However, expression of the CVB3 capsid protein VP1 dramatically increased in the HeLa cells overexpressing MAGI-3 24 h after CVB3 infection. In addition, the activities of AKT and ERK were significantly induced in the CVB3-infected MAGI-3 cells overexpressing HeLa. These results demonstrate that MAGI-3 expression upregulates CVB3 replication through AKT and ERK signaling activation. MAGI-3 may be an important target to control CVB3 replication.