• Archives of Pharmacal Research
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• v.21 no.6
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• pp.712-717
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• 1998

The complete nucleotide sequence of the cDNA clone encoding rat skeletal muscle myosin- binding protein H (MyBP-H) was determined and amino acid sequence was deduced from the nucleotide sequence (GenBank accession number AF077338). The full-length cDNA of 1782 base pairs(bp) contains a single open reading frame of 1454 bp encoding a rat MyBP-H protein of the predicted molecular mass 52.7kDa and includes the common consensus 1CA__TG' protein binding motif. The cDNA sequence of rat MyBP-H show 92%, 84% and 41% homology with those of mouse, human and chicken, respectively. The protein contains tandem internal motifs array (-FN III-Ig C2-FN III- Ig C2-) in the C-terminal region which resembles to the immunoglobulin superfamily C2 and fibronectin type III motifs. The amino acid sequence of the C-terminal Ig C2 was highly conserved among MyBPs family and other thick filament binding proteins, suggesting that the C-terminal Ig C2 might play an important role in its function. All proteins belonging to MyBP-H member contains `RKPS` sequence which is assumed to be cAMP- and cGMP-dependent protein kinase A phosphorylation site. Computer analysis of the primary sequence of rat MyBP-H predicted 11 protein kinase C (PKC)phosphorylation site, 7 casein kinase II (CK2) phosphorylation site and 4N-myristoylation site.

• BMB Reports
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• v.33 no.2
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• pp.103-111
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• 2000

Phosphorylation of the eukaryotic elongation factor 2 (eEF-2) blocks the elongation step of translation and stops overall protein synthesis. Although the overall rate of protein synthesis in mitosis reduces to 20% of that in S phase, it is unclear how the protein translation procedure is regulated during the cell cycle, especially in the stage of peptide elongation. To delineate the regulation of the elongation step through eEF-2 function, the changes in phosphorylation of eEF-2, and in activity of corresponding $Ca^{2+}$/calmodulin (CaM)-dependent protein kinase III (CaMK-III) during the cell cycle of NIH 3T3 cells, were determined. The in vivo level of phosphorylated eEF-2 showed an 80% and 40% increase in the cells arrested at G1 and M, respectively. The activity of CaMK-III also changed in a similar pattern, more than a 2-fold increase when arrested at G1 and M. The activity change of the kinase during one turn of the cell cycle also demonstrated the activation at G1 and M phases. The activity change of cAMP-dependent protein kinase (PKA) was reciprocal to that of CaMK-III. These results indicated: (1) the activity of CaMK-III was cell cycle-dependent and (2) the level of eEF-2 phosphorylation followed the kinase activity change. Therefore, the elongation step of protein synthesis might be cell cycle dependently regulated.

• The Korean Journal of Zoology
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• v.35 no.2
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• pp.161-172
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• 1992

In the short-term treahent of 12-0-tetradecanoylphorbol-13-acetate (TPA) or platelet-derived growth factor (PDGF), the'Wh and PDGF induced the Protein Kinase C (PKC) activation and migration from the cytoplasm to the peripheral nulcear membrane. And the activated PKC which was directly or indirectly stimulated by TPA or PDGF Phosphorylated many kinds of PKC's targeting proteins and induces various biological responses. Especially, the cytoplasmic PKC was phosphorylated within 1 hr and 10 min by TPA-and PDGF-treahent respectivelv. In the long-term treatment of TPA or PDGF, both of them induced the down-regulation and translocation of PKC in the mvoblasts. The down-regulation of PKC isozyrnes, the pattern of PKC I and ll was similar to the PKC 111 isozpnes in the cytoplasm. But in the nucleolus, the TPA did not induce and down-regulation or the inhibition of the immunoreactivity of PKC III antibody. This investigation indicates that each isozvmes of PKC mal be performed the different effects to the down-regulation of the cytoplasm or nucleolus. And douvn-regulated myoblasts contained low immunoreactivity of PKC antibodies.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.131-141
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• 1991

Treating 12-O-tetradecanoyIphorboI 13-acetate -TPA) or platelet~derived growth factor(PDGF), the signal transduction of protein Idnase C (PKC) is occurred by the phosphoryladon. However the targeting proteins phosphorylated by PKC were found to be different proteins in molecular weights when WA or PDGF wa~ treated to the myoblast. In the WA-treated myoblast cells, the protein of Mr. 20 I(d was phosphorylated. In the PDGF-treated cells, the protein of Mr. 40 Kd was phosphrylated, while the protein of Mr. 20 Kd which phosphorylated in the WA-treatment was dephosphorylated. These results indicate that not only WA and PDGF &e different in activating the signal transduction pathways, but also they may involve in the down reguladon of PI(C during the long-term treatment But PDGF gave rise more rapidly down reguladon than in the case of WA. Using immunocytochemical approach, two disdnct PKC isozymes, PKC II and PKC III, have been localized in cytoplasm and both cytoplasm and nuclsolus, respectively. Ther'efore, the expression of two types of PKC in the myoblast suggests that the isozymes of PKC may involve in each different pathway of signal transduction or down-reguladon.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1227-1234
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• 2011

We investigated the immunostimulatory effects of doenjang, a famous Korean traditional food made from fermented soybean paste, on the immunohistochemical reaction in the gastrointestinal (GI) tract and immune response in mice. Male C57BL/6N mice (6 weeks-old) were divided into 4 experimental diet treatment groups and a basal diet (control) group, and fed with different diets for 4 weeks. The immunoreactive density of $CD4^+/CD8^+$ lymphocytes were strongly stained in the jejunum and colon in Group III. The immunoreactivity of universal nitric oxide synthase (uNOS) was strongly stained in the myenteric plexus in the colon of all doenjang-fedgroups (I, II and III). The colonic immunoreactive density of protein kinase C-${\alpha}$ (PKC-${\alpha}$) was strongly increased in Groups II and III, while that of stem-cell factor (c-kit) was increased in colonic mucosa of all doenjang-fedgroups (I, II and III) and especially increased in the colonic muscle layer of Group III. These morphological and immunological results indicated that the intake of doenjang could improve the mucosal immune reaction, gastrointestinal motility, blood circulation in the GI tract, and the immuneactivity of the body. These results provide experimental evidence about the health benefits of doenjang.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.173-178
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• 1995

동물계에서 항바이러스와관련된 dsRNA 의존성 인산화 효소(PKR)의 유전자를 식물체에서 발현시킬 경우 PKR에 의한 단백질합성 및 식물바이러스의 증식조절 가능성에 대한 기초자료를 확보하기 위하여 사람에서 분리된 PKR cDNA를 Agrobacterium 방법에 의하여 연초식물체(Nicotiana tabacum cv. Xanthi-nc)로 형질전환시켰다. HindIII/PstI처리에 의해 얻어지는 약 1.8kb의 phPKR cDNA절편을 일련의 유전자 조작 방법을 통하여 식물발현벡터인 pBI121에 도입하여, p12168을 재조합하였다. 이를 A. tumefaciens LBA 4404에 형질전환시켜 연초식물체형질 전환에 이용하였다. 2mg/l BA와 0.5mg/l NAA가 포함되고 100$\mu\textrm{g}$/ml의 kanamycin이 첨가된 MS배지에서 shooting시킨 후 phytohormone이 첨가되지 않은 MS배지상에서 rooting을 시켜 형질전환 연초식물체를 얻었으며, 형질전환식물체는 정상식물체와 유사한 생육양상을 나타내었다. 형질전환식물체의 유전자도입은 hPKR cDNA의 전사부여는 RT-PCR 방법에 의하여 확인되었다.

• Molecules and Cells
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• v.21 no.1
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• pp.21-28
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• 2006

The interferon-induced, double-stranded RNA (dsRNA)-dependent protein kinase PKR plays a key role in interferon-mediated host defense against viral infection, and is implicated in cellular transformation and apoptosis. We have isolated a cDNA of simian PKR encoding a product with 83% amino acid identity to the human homolog and showed that PKR expression is significantly attenuated in the Vero E6 African green monkey kidney cells devoid of type I interferon genes. A variant form of PKR lacking the exon 12 in the kinase domain is produced in these cells, presumably from an alternatively spliced transcript. Unlike wild type PKR, the variant protein named PKR-${\Delta}E12$ is incapable of auto-phosphorylation and phosphorylation of eIF2-${\alpha}$, indicating that the kinase sub-domains III and IV embedded in exon 12 are indispensable for catalytic function. PKR-${\Delta}E12$ had no dominant negative effect but was weakly phosphorylated in trans by wild type PKR.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.3
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• pp.345-352
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• 2017

Since previous studies have reported that hydroquinone (HQ) exerted immunosuppressive and anti-inflammatory activity, various HQ derivatives have been synthesized and their biological activities investigated. In this study, we explored the anti-inflammatory activity of JS-III-49, a novel HQ derivative, in macrophage-mediated inflammatory responses. JS-III-49 suppressed the production of the inflammatory mediators nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) and down-regulated the mRNA expression of the inflammatory enzymes cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) as well as the expression of the pro-inflammatory cytokines interleukin-6 (IL-6) and IL-$1{\beta}$ without cytotoxicity in LPS-stimulated RAW264.7 cells. JS-III-49 inhibited nuclear translocation of the $NF-{\kappa}B$ transcription factors p65 and p50 by directly targeting Akt, an upstream kinase of the $NF-{\kappa}B$ pathway, in LPS-stimulated RAW264.7 cells. However, JS-III-49 did not directly inhibit the kinase activities of Src and Syk, which are upstream kinases of Akt, in LPS-stimulated RAW264.7 cells. Moreover, JS-III-49 suppressed the nuclear translocation of c-Fos, one of the components of AP-1, by specifically targeting p38, an upstream mitogen-activated protein kinase (MAPK) in the AP-1 pathway in LPS-stimulated RAW264.7 cells. These results suggest that JS-III-49 plays an anti-inflammatory role in LPS-stimulated macrophages by targeting Akt and p38 in the $NF-{\kappa}B$ and AP-1 pathways, respectively.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.279-285
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• 2015

Background: Korean Red Ginseng has been used as a traditional oriental medicine to treat illness and to promote health for several thousand years in Eastern Asia. It is widely accepted that ginseng saponins, ginsenosides, are the major active ingredients responsible for Korean Red Ginseng's therapeutic activity against many kinds of illness. Although the crude saponin fraction (CSF) displayed antiplatelet activity, the molecular mechanism of its action remains to be elucidated. Methods: The platelet aggregation was induced by collagen, the ligand of integrin ${\alpha}_{II}{\beta}_I$ and glycoprotein VI. The crude saponin's effects on granule secretion [e.g., calcium ion mobilization and adenosine triphosphate (ATP) release] were determined. The activation of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated protein kinase 1/2 (ERK1/2), c-Jun N-terminal kinases (JNKs), and p38 MAPK, and phosphoinositide 3-kinase (PI3K)/Akt was analyzed by immunoblotting. In addition, the activation of integrin ${\alpha}_{II}b{\beta}_{III}$ was examined by fluorocytometry. Results: CSF strongly inhibited collagen-induced platelet aggregation and ATP release in a concentration-dependent manner. It also markedly suppressed $[Ca^{2+}]_i$ mobilization in collagen-stimulated platelets. Immunoblotting assay revealed that CSF significantly suppressed ERK1/2, p38, JNK, PI3K, Akt, and mitogen-activated protein kinase kinase 1/2 phosphorylation. In addition, our fraction strongly inhibited the fibrinogen binding to integrin ${\alpha}_{IIb}{\beta}_3$. Conclusion: Our present data suggest that CSF may have a strong antiplatelet property and it can be considered as a candidate with therapeutic potential for the treatment of cardiovascular disorders involving abnormal platelet function.

• Molecules and Cells
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• v.22 no.3
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• pp.291-299
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• 2006

Vitexin, a natural flavonoid compound identified as apigenin-8-C-${\beta}$-D-glucopyranoside, has been reported to exhibit antioxidative and anti-inflammatory properties. In this study, we investigated its effect on hypoxiainducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) in rat pheochromacytoma (PC12), human osteosarcoma (HOS) and human hepatoma (HepG2) cells. Vitexin inhibited HIF-$1{\alpha}$ in PC12 cells, but not in HOS or HepG2 cells. In addition, it diminished the mRNA levels of hypoxia-inducible genes such as vascular endothelial growth factor (VEGF), smad3, aldolase A, enolase 1, and collagen type III in the PC12 cells. We found that vitexin inhibited the migration of PC12 cells as well as their invasion rates, and it also inhibited tube formation by human umbilical vein endothelium cells (HUVECs). Interestingly, vitexin inhibited the hypoxia-induced activation of c-jun N-terminal kinase (JNK), but not of extracellular-signal regulated protein kinase (ERK), implying that it acts in part via the JNK pathway. Overall, these results suggest the potential use of vitexin as a treatment for diseases such as cancer.