• Archives of Pharmacal Research
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• v.16 no.2
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• pp.114-117
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• 1993

Ginsenosides present in the roots of panax ginseng C.A. Meyer were shown to induce a stimulatory effect on the overexpressed cellular chicken c-src protein tyrossine kinase in NH3T3 cells. Among 4 ginsenosides studied $(G-Rb_2,\;G-Rc,\;G-Re\;and\;G-Rg_1),\;G-Rg_1$ showed the most stimulatory effect at $16.7\mu{g/ml}$ ginsenoside concentration increasing the activity by 2-4 times. Inhibitors of either protein synthesis or RNA synthesis blocked the activation of c-src proein tyrosine kinase. These results suggest that the csrc kinase activation apprars to involve an increase in the amount of protein of the kinase by transcriptional control mechanism rather than an increase in the kinase activity.

• Tuberculosis and Respiratory Diseases
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• v.53 no.6
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• pp.595-611
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• 2002

Akt/PKB protein kinase B, ALI acute lung injury, ARDS acute respiratory distress syndrome, CREB C-AMP response element binding protein, ERK extracelluar signal-related kinase, fMLP fMet-Leu-Phe, G-CSF granulocyte colony-stimulating factor, IL interleukin, ILK integrin-linked kinase, JNK Jun N-terminal kinase, LPS lipopolysaccharide, MAP mitogen-activated protein, MEK MAP/ERK kinase, MIP-2 macrophage inflammatory protein-2, MMP matrix metalloproteinase, MPO myeloperoxidase, NADPH nicotinamide adenine dinucleotide phosphate, NE neutrophil elastase, NF-kB nuclear factor-kappa B, NOS nitric oxide synthase, p38 MAPK p38 mitogen activated protein kinase, PAF platelet activating factor, PAKs P21-activated kinases, PMN polymorphonuclear leukocytes, PI3-K phosphatidylinositol 3-kinase, PyK proline-rich tyrosine kinase, ROS reactive oxygen species, TNF-${\alpha}$ tumor necrosis factor-a.

• Journal of Life Science
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• v.17 no.10
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• pp.1361-1367
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• 2007

I investigated the effect of KT5720, an inhibitor of protein kinase A, on the vesicular stomatitis virus (VSV) infection in BHK-21cell cultures. The virus inducted cytopathic effect (CPE) was almost completely suppressed by KT5720 at 5uM. The inhibitor, however, did not affect replication of the virus nor the synthesis of viral macromolecules. KT5720, did not block the cytoskeletal disruption, while the cell rounding was suppressed. And, the KT5720-sensitive function may be involved in developing the VSV-induced CPE, but not essential for the virus replications.

• Bioinformatics and Biosystems
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• v.2 no.1
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• pp.28-32
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• 2007

The protein phosphorylation is one of the important processes in the cell signaling pathway. A variety of protein kinase families are involved in this process, and each kinase family phosphorylates different kinds of substrate proteins. Many methods to predict the kinase-specific phosphoryrated sites or different types of phosphorylated residues (Serine/Threonine or Tyrosin) have been developed. We employed Supprot Vector Machine (SVM) to attempt the prediction of protein kinase specific phosphorylation sites. 10 different kinds of protein kinase families (PKA, PKC, CK2, CDK, CaM-KII, PKB, MAPK, EGFR) were considered in this study. We defined 9 residues around a phosphorylated residue as a deterministic instance from which protein kinases determine whether they act on. The subsets of PSI-BALST profile was converted to the numerical vectors to represent positive or negative instances. When SVM training, We took advantage of multiple SVMs because of the unbalanced training sets. Representative negative instances were drawn multiple times, and generated new traing sets with the same positive instances in the original traing set. When testing, the final decisions were made by the votes of those multiple SVMs. Generally, RBF kernel was used for the SVMs, and several parameters such as gamma and cost factor were tested. Our approach achieved more than 90% specificity throughout the protein kinase families, while the sensitivities recorded 60% on average.

• BMB Reports
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• v.30 no.2
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• pp.89-94
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• 1997

In this study, during the activation of neutrophil responses by sodium fluoride. involvement of protein tyrosine kinase was studied. Respiratory burst lysosomal enzyme release and elevation of $[Ca^{2+}]_i$stimulated by sodium fluoride in neutrophils were inhibited by protein kinase inhibitors, genistein and tyrphostin. The inhibitory effect of genistein and tyrphostin on superoxide and $H_{2}O_{2}$ production was less than that of protein kinase C inhibitors, staurosporine and H-7. Staurosporine and H-7 had little or no effect on the release of myeloperoxidase and acid phosphatase stimulated by sodium fluoride. EGTA and verapamil inhibited the elevation of $[Ca^{2+}]_i$ evoked by sodium fluoride. The inhibitory effect of staurosporine on the elevation of $[Ca^{2+}]_i$ was less than that of genistein. Phorbol 12-myristate 13-acetate (PMA)-stimulated superoxide production, which is sensitive to staurosporine, was further enhanced by genistein, whereas the stimulatory action of PMA on myeloperoxidase release was inhibited by genistein. A pretreatment of neutrophils with PMA signifcantly attenuated sodium fluoride-evoked elevation of $[Ca^{2+}]_i$ These results suggest that protein tyrosine kinase may be involved in the activation process of neutrophil responses due to direct stimulation of guanine nucleotide regulatory proteins. In neutrophil responses, PMA-stimulated neutrophils appear to show a different type of inhibition of protein tyrosine kinase.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1069-1075
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• 2004

In an attempt to evaluate the function of MAP kinase in porcine oocytes and to develop a method of the assessment of its activity, myelin basic protein (MBP) was used as a substrate to detect the MAP kinase activity of porcine oocytes which had undergone maturation in vitro. The existence of MAP kinase and MAP kinase kinase (MAPKK) was verified in immature porcine germinal vesicle (GV) oocytes at 0 h culture via Western blotting. Porcine oocytes exhibited a low level of MAP kinase activity during the first 20 h of culture, which increased at 25 h, during which time a breakdown in the nuclear membrane occurred. Significantly higher increases (p<0.05) of MAP kinase activity were detected at 30 h of culture. Using the gel phosphorylation method, MBP was phosphorylated at two positions corresponding to mammalian MAP kinase-extracellular signal-regulated kinase (ERK 1) (44 kDa) and ERK 2 (42 kDa). The absolute levels of those proteins did not increase during 40 h of culture, suggesting that the detected increase in MAP kinase activity was the result of phosphorylation rather than changes in the total amount of protein. MAPKK and MAP kinase were dephosphorylated in first-stage (MI) meiotic oocytes by the addition of cycloheximide, a protein synthesis inhibitor. These results of this study indicate that the MAP kinase cascade does exists in porcine oocytes and that its activation leads to oocyte maturation.

• Journal of Photoscience
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• v.7 no.3
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• pp.123-128
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• 2000

Phosphorylation of cellular proteins is a key regulatory mehanism for signal transduction pathway in living cells. Phytochrome, a red/far-red light photoreceptor in plants, is known to employ protein phosphorylation for its light signaling, although its detauked mechanism is still ambiguous. This study is intended to identify the phosphoproteins and protein kinases that are regulated by phytochrome, by employing transgenic rice seedlings that overexpress Arabidopsis phytochrome A. Red light stimulated phsophorylation of a 70 kDa protein and far-red light negated the effect. The red light induced phosphotylation of the 70 kDa protein was strongly activated by heparin and inhibited by poly-L-lysine, suggesting that the 70 kDa protein phosphorylating kinase belongs to GSK-3/SHAGGY protein kinase that has functional roles in establishing cell fate and pattern formation in Drosophila. Taken together with the fact that phytochrome controls plant development, these results may suggest that a GSK-3/SHAGGY-related protein kinase in plant(ASK) is likely to be involved in phytochrome signal transduction.

• Journal of Ginseng Research
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• v.22 no.2
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• pp.133-139
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• 1998

We have studied an activation mechanism of $pp60^{c-src}$ protein tyroslne kinase (PTK) by ginsenoside-$Rg_1$ (G-$Rg_1$ ) in NIH(pMcsrc/foc)B c-src overexpressor cells. It was previously reported that G--$Rg_1$ stimulated the activation of c-src kinase at 20 pM with a 18 hr-incubation, increasing the activity by 2-4-fold over that of untreated control, and this effect was blocked by treatments of in- hibitors of either protein synthesis (cycloheximide) or RNA synthesis (actinomycin D) (Hong, H.Y. et at. Arch. Pharm. Res. 16, 114 (1993)). However, an amount of c-src protein itself in wild-type cells was not changed by G-$Rg_1$. When the cells mutated at one or two tyrosine residue(s) (Y416/527) that are important sites to regulate the kinase activity were treated with G-$Rg_1$, increases both in the activity of c-src kinase and in the expression of the protein were not observed. In addition, removal of extracellular calcium ion by EGTA or inhibition of PKC by H-7 canceled the G-$Rg_1$-induced activation of the kinase. Although the activation was little affected by G-$Rg_1$ with a calcium ionophore A23187, it was synergistically stimulated by treatment of G-Rgl and PMA, a PKC activator. Taken together, these results suggest that the activation of c-src kinase by G-$Rg_1$ is caused by an increase in the specific activity of the kinase, but not in amount of it, and is involved with both collular calcium ion and PKC. Further the increase in the specific activity of c-src kinase may result from altered phosphorylation at tyro-416 and -527.

• Rapid Communication in Photoscience
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• v.2 no.2
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• pp.56-59
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• 2013

Plant phytochromes, molecular light switches that regulate various aspects of plant growth and development, are known as autophosphorylating serine/threonine kinases. Although recent studies reveal that phytochrome autophosphorylation plays an important role in the regulation of phytochrome signaling through the control of phyA protein stability, the in vivo functional roles of phytochrome kinase activity in plant light signaling are largely unknown. Thus, it is necessary to investigate the detailed function of phytochrome as a protein kinase, which might include mapping of kinase domain on the phytochrome molecule, searching for substrates that could be phosphorylated by phyA, and in vivo functional analysis of the kinase activity with phytochrome mutants displaying reduced kinase activity. Our recent studies reveal that the kinase activity of phytochrome plays a positive role in plant light signaling. Therefore, we highlight the current knowledge about the functional roles of phytochrome kinase activity in the light signal transduction of plants, based on our recent results.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.123-127
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• 1996

Secretion of surfactant phospholipid can be stimulated by a variety of agonists acting via at least three different signal transduction mechanisms. These include the adenylate cyclase system with activation of cAMP-dependent protein kinase; activation of protein kinase C either directly or subsequent to activation of phosphoinositide-specific phospholipase C and generation of diacylglycerols and inositol trisphosphate; and a third mechanism that involves incresed $Ca^{2+}$ levels and a calmodulin-dependent step. ATP stimulates secretion via all three mechanisms. The protein kinase C pathway is also coupled to phopholipase D which, acting on relatively abundant cellular phospholipids, generates diacylglycerols that further activate protein kinase C. Sustained protein kinase C activation can maintain phosphatidylcholine secretion for a prolonged period of time. It is likely that interactions between the different signaling pathways have an important role in the overall physiological regulation of surfactant secretion.