• Journal of Microbiology
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• 제34권4호
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• pp.374-378
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• 1996

In the aquatic fungus Allomyces macrogynus the effects of $Ca^{2+}$ and cAMP on the intracellular signal transduction of zoospore germination were studied using in vitro protein phosphorylation assay system. An endogenously phosphorylated protein (p50) having molecular weight of 50 kDa on SDS-PAGE was found in soluble fractions of both zoospore and mycelium. In zoospore extract, the endogenous phosphorylation of p50 was weak without any effectors, but was enhanced by $Ca^{2+}$ and even more by cAMP. Phosphorylation of the same protein in mycelial extract was high only in the absence of cAMP. Irrespective of the presence of $Ca^{2+}$ and cAMP, its phosphorylation was antagonistically suppressed in assay of combined zoospore and mycelial extracts. These results suggest that p50 is interconvertible in phosphorylation/dephosphorylation as a novel protein involved in germination of A. macrogynus. The antagonistic effect of cAMP to the phosphorylation of p50s from different developmental stages may be important in the regulation of cellular differentiation.

• Journal of Ginseng Research
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• 제20권3호
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• pp.219-225
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• 1996

This study was performed to investigate the inhibition mechanism of cancer cell proof iferation caused by the petroleum-ether extract of ginseng against human rectum (HRT-18), colon (HT-29), llepatoma (Hep G2) and prostate (LNCaP) cancer cells and monkey kidney cells (Vero 76). Cells were treated with the petroleum-ether extract of ginseng (50 to 200 $\mu\textrm{g}$/ml) in G1 or S phase of the cell cycle, and proliferation and protein kinase C activity were measured. The petroleum-eth or extract of ginseng inhibited proliferation of HRT-18, HT-29, Hep G2 and LNCaP when treated in Gl phase, but not in S phase. This result shows that the ginseng extract arrests the cell cycle in G1 phase, resulting in the inhibition of cell proliferation. At the same concentrations, treatment of the ginseng extract in G1 phase decreased protein kinase C activity, while the treatment in S phase had no effect. This reault suggests that protein kinase C might be involved in the inhibition of the cell cycle and proliferation of cancer cells caused by the petroleum-ether extract of ginseng.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1985년도 워크샵 및 심포지엄 북한산국립공원의 식생
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• pp.7-18
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• 1985

Light-regulated translation of chloroplast mRNAs requires nuclear-encoded trans-acting factors that interact with the 5' untranslated region (UTR) of these mRNAs. A set of four proteins (60, 55, 47, and 38 kDa) that bind to the 5'-UTR of the psbA mRNA had been identified in C. reinhardtii. 47 kDa protein (RB47) was found to encode a chloroplast poly (A)-binding protein (cPABP) that specifically binds to the 5'-UTR of the psbA mRNA, and essential for translation of this mRNA, cDNA encoding 60 kDa protein (RB60) was isolated, and the amino acid sequence of the encoded protein was highly homologous to plants and mammalian protein disulfide isomerases (PDI), normally found in the endoplasmic reticulum (ER). Immunoblot analysis of C. reinhardtii proteins showed that anti-PDI recognized a distinct protein of 56 kDa in whole cell extract, whereas anti-rRB60 detected a 60 kDa protein. The ER-PDI was not retained on heparin-agarose resin whereas RB60 was retained. In vitro translation products of the RB60 cDNA can be transported into C. reinhardtii chloroplast in vitro. Immunoblot analysis of isolated pea chloroplasts indicated that higher plant also possess a RB60 homolog. In vitro RNA-binding studies showed that RB60 modulates the binding of cPABP to the 5'-UTR of the psbA mRNA by reversibly changing the redox status of cPABP using redox potential or ADP-dependent phosphorylation. Site-directed mutagenesis of -CGHC- catalytic site in thioredoxin-like domain of RB60 is an unique PDI located in the chloroplast of C. reinhardtii, and suggest that the chloroplast PDI may have evolved to utilize the redox-regulated thioredoxin like domain as a mechanism for regulating the light-activated translation of the psbA mRNA.

• 한국치위생학회지
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• 제20권3호
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• pp.303-312
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• 2020

Objectives: The purpose of this study was to investigate the relationship between periodontal disease, number of remaining teeth with high-sensitivity C-Reactive protein in Korean adults aged 40 and older. Methods: The study used the Sixth Korea National Health and Nutrition Examination Survey (KNHANES VI-3), 2015. The study sample consisted of 3,883 aged 40 years or older who had completed the health survey and the health examination. Logistic regression analyses were performed to examine the odds ratios of high-sensitivity C-Reactive protein by periodontal disease and number of remaining teeth, adjusting for demographic characteristics, chronic diseases and oral health behavior-related variables. Results: When the demographic and chronic diseases were adjusted, the risk of high-sensitivity C-Reactive protein (hs-CRP) average 1.23 mg/L or higher was 1.36 times higher in patients with periodontal disease between the ages of 40 and 49, but it was not significant (OR=1.36; 95% CI=0.82-2.23). In addition, in the group of 0~23 remaining teeth aged 40~49 years, the risk of higher than the average 1.23 mg/L of high-sensitivity C-Reactive protein was 2.03 times higher (OR=2.03; 95% CI=1.10-3.74), and 1.49 times higher in 60~69 years (OR=1.07; 95% CI=1.04-2.76). Conclusions: This study found that periodontal disease and tooth loss in Korean adults aged 40 and older was significantly associated with high-sensitivity C-reactive protein.

• 한국동물학회지
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• 제34권2호
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• pp.131-141
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• 1991

TPA나 PDGF를 처리로 인한 Protein Kinase C의 신호전달은 힌산화에 의해 일어난다. 그렇지만, PKC에 의해 인산화 되어지는 targeting protein은 TAP나 PDGF 처리시에는 분자량이 서로 다른 단백질들이 인산화가 되어졌다. TPA처리한 myoblast에서 분자량 20,000의 단백질이 인산화되었다. PDGF처리한 세포에서는 분자량 40,000의 단백질이 인산화된 반면에 TPA처리로 인산화 되었던 분자량 20,000의 단백질은 탈인산화 되었다. 이러한 결과들은 TPA와 PDGF가 신호전달계의 활성에 있어서 다를 뿐만 아니라 그들은 장시간의 처리동안 PKC의 down regulation에 관계되어 짐을 암시한다. 그러나 PDGF는 TPA의 경우에서 보다 빠른 down regulation을 유도하였다. 면역세포 화학적인 연구에서 PKC의 동위효소인 PKC II는 세포질에, PKC III는 세포질과 인에 각각 분포하고 있었다. Myoblast에 있어서 PCK두가지 형태의 동위효소의 발현은 이들 동위효소들이 signal transduction이나 down regulation의 각기 다른 경로에 개입되어 진다는 것을 암시한다.

• BMB Reports
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• 제33권1호
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• pp.59-62
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• 2000

Hepatitis C virus (HCV) nonstructural 5B (NS5B) protein is an RNA-dependent RNA polymerase (RdRp). To determine whether it can contribute to viral replication by interaction with cellular proteins, the yeast two-hybrid screening system was employed to screen a human liver cDNA library. Using the HCV NS5B as a bait, we have isolated positive clones encoding a cellular protein. The NS5B interacting protein, 5BIP, is a novel cellular protein of 170 amino acids. Interaction of the HCV NS5B protein with 5BIP was confirmed by a protein-protein blotting assay. Recently, we have demonstrated that NS5B possesses an RdRp activity and thus it is possible that 5BIP, in association with NS5B, plays a role in HCV replication.

• 동의신경정신과학회지
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• 제21권2호
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• pp.191-200
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• 2010

Objectives : This experiment was designed to investigate the effect of Chongmyung-Tang Prescription Combination(CmTP-$C_{1-10}$) extract on the production of amyloid $\beta$ protein and $\beta$-site amyloid precursor protein-cleaving enzyme(BACE) activity. Methods : The effect of CmTP-$C_{1-10}$ extract on expression of APP mRNA, BACE2 mRNA in BV2 microglia cell line treated by lipopolysacchride(LPS) and amyloid $\beta$ protein fragment(A$\beta$ fragment) were investigated. The effect of CmTP-$C_{1-10}$ extract on production of amyloid $\beta$ protein(A$\beta$) in BV2 microglia cell line treated by LPS and A$\beta$ fragment were investigated. The effect of CmTP-$C_{1-10}$ extract on BACE activity were investigated. Results : 1. CmTP-$C_9$ extract the most significantly suppressed the expression of APP mRNA, BACE2 mRNA in BV2 microglia cell line treated by LPS and A$\beta$ fragment. 2. CmTP-$C_9$ extract significantly suppressed the production of A$\beta$ in BV2 microglia cell line treated by LPS and A$\beta$ fragment. 3. CmTP-$C_9$ extract the most significantly inhibited BACE activity. Conclusions : These results suggest that CmTP-$C_9$ may be effective for the prevention and treatment of Alzheimer's Disease. Investigation into clinical use of CmTP-$C_9$ for Alzheimer's Disease is suggested for future research.

• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.233-239
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• 1997

A mammary epithelial cell line (MAC-T) established as a model for lactation was utilized to identify and characterize effects of various hormones upon insulin-like growth factor binding protein secretion. Ligand and immunoblot analyses of conditioned media indicated that insulin-like growth factor binding protein-2 was secreted by MAC-T cells. Insulin-like growth factor-I stimulated insulin-like growth factor binding protein-2 secretion in a dose-dependent manner, but prolactin and bovine somatotropin did not alter insulin-like growth factor binding protein-2 secretion. Insulin increased and cortisol decreased insulin-like growth factor binding protein-2 secretion. Effects of insulin-like growth factor-I on insulin-like growth factor binding protein-2 secretion support previous studies using primary cultures of bovine mammary cells and bovine fibroblasts. Effects of cortisol and insulin on insulin-like growth factor binding protein-2 secretion may be explained by changes in protein synthesis. In addition, supraphysiological doses of insulin can cross-react with the insulin-like growth factor-I receptor and stimulate insulin-like growth factor binding protein-2 secretion. MAC-T cells provide a model system to study mechanisms that regulate local insulin-like growth factor-I bioactivity.

• Journal of Microbiology
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• 제33권3호
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• pp.191-195
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• 1995

IciA protein has been shown as an inhibitor for the initiation of E. coli chromosomal DNA replication at oriC. IciA protein binds the AT-rich region in oriC and then blocks the initiation of chromosomal DNA replication. Two binding sites for IciA protein were identified in dnaA gene, encoding the initiator for the E. coli chromosomal replication, promoter region by gel-shift assay and DNase I footprinting, One, named as IciA site I, is located upstream of the dnaA promoter 1P. The other, named as IciA site II, is located downstream of the dnaA promoter 2P. The sequence comparison of the regions protected from the DNase I cleavage did not result in a clear consensus sequence for the binding of IciA protein, suggesting that IciA protein may be a member of multimeric complex dsDNA binding proteins. This study provided information about the binding mode of IciA protein. Even though the IciA site II and IciA binding site in oriC seem to be composed of two IciA binding units, one binding unit is likely enough to cause the binding of IciA protein to the IciA site I. The binding of IciA protein to the dna4 promoter implies that IciA protein may involve not only the control of the initiation of chromosomal DNA replication but also the control of the dna4 gene expression.

• 약학회지
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• 제45권4호
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• pp.426-430
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• 2001

Cells are eliminated in a variety of physiological settings by apoptosis, a genetically encoded process of cellular suicide. Bak, a member of the Bcl-2 protein family, accelerates apoptosis by an unknown mechanism. We have found a novel cDNA encoding a 101 amino acid protein possessing a Bak-like in our full-length cDNA bank. Bak-like shares the conserved domains BHI and 2 with other proapoptotic proteins but lacks the BH3 domain. Bak-like is expressed in a wide variety of tissues. Like Bak, Bak-like gene product primarily enhances apoptotic cell death following an appropriate stimulus.