• 제목/요약/키워드: protein kinase C

검색결과 1,396건 처리시간 0.031초

Involvement of Protein Tyrosine Kinase in Stimulated Neutrophil Responses by Sodium Fluoride

  • Chung, Ki-Kwang;Han, Eun-Sook;Lee, Chung-Soo
    • BMB Reports
    • /
    • 제30권2호
    • /
    • pp.89-94
    • /
    • 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.

  • PDF

Endosulfan Induces CYP1A1 Expression Mediated through Aryl Hydrocarbon Receptor Signal Transduction by Protein Kinase C

  • Han, Eun Hee;Kim, Hyung Gyun;Lee, Eun Ji;Jeong, Hye Gwang
    • Toxicological Research
    • /
    • 제31권4호
    • /
    • pp.339-345
    • /
    • 2015
  • CYP1A1 is a phase I xenobiotic-metabolizing enzyme whose expression is mainly driven by AhR. Endosulfan is an organochlorine pesticide used agriculturally for a wide range of crops. In this study, we investigated the effect of endosulfan on CYP1A1 expression and regulation. Endosulfan significantly increased CYP1A1 enzyme activity as well as mRNA and protein levels. In addition, endosulfan markedly induced XRE transcriptional activity. CH-223191, an AhR antagonist, blocked the endosulfan-induced increase in CYP1A1 mRNA and protein expression. Moreover, endosulfan did not induce CYP1A1 gene expression in AhR-deficient mutant cells. Furthermore, endosulfan enhanced the phosphorylation of calcium calmodulin (CaM)-dependent protein kinase (CaMK) and protein kinase C (PKC). In conclusion, endosulfan-induced up-regulation of CYP1A1 is associated with AhR activation, which may be mediated by PKC-dependent pathways.

Bradykinin-Mediated Stimulation of Phospholipase D in Rabbit Kidney Proximal Tubule Cells

  • Park, Kyung-Hyup;Jung, Jee-Chang;Chung, Sung-Hyun
    • Biomolecules & Therapeutics
    • /
    • 제2권1호
    • /
    • pp.39-46
    • /
    • 1994
  • The present study was undertaken to demonstrate whether or not bradykinin activates a phospholipase D in rabbit kidney proximal tubule cells. By measuring the formation of [$^3$H]phosphatidic acid and [$^3$H]phosphatidylethanol we could elucidate the direct stimulation of phospholipase D by bradykinin. Bradykinin leads to a rapid increase in [$^3$H]phosphatidic acid and [$^3$H]diacylglycerol, and [$^3$H]phosphatidic acid formation preceded the formation of [$^3$H]diacylglycerol. This result suggests that some phosphatidic acid seems to be formed directly from phosphatidylcholine by the action of phospholipase D, not from diacylglycerol by the action of diacylglycerol kinase. In addition, the other mechanisms by which phospholipase D is activated was examined. We have found that phospholipase D was activated and regulated by extracellular calcium ion and pertussis toxin-insensitive G protein, respectively. It has also been shown that bradykinin may activate phospholipase D through protein kinase C-dependent pathway. In conclusion, we are now, for the first time, strongly suggesting that bradykinin-induced activation of phospholipase D in the rabbit kidney proximal tubule cells is mediated by a pertussis toxin-insensitive G protein and is dependent of protein kinase C.

  • PDF

근세포 분화에 관한 연구 : 근세포 분화에 있어서 Protein Kinase C (Studies on the Differentiation of Skeletal Muscle Cells in vitro:Protein Kinase C in the Differentiation of Skeletal Muscle Cells)

  • 최원철;김한도;김정락
    • 한국동물학회지
    • /
    • 제34권2호
    • /
    • pp.131-141
    • /
    • 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.

  • PDF

밤바구미(Curculiodentipes) 유충의 cyclic AMP 농도와 CAMP-dependent protein kinase 활성도 변화 (concentration of cyclic AMP and activity of cyclic AMP-dependent Protein Kinase in Chestnut Weevil, Curculio dentipes)

  • 류진수;김유경이경로
    • 한국동물학회지
    • /
    • 제37권2호
    • /
    • pp.222-231
    • /
    • 1994
  • 밤바구미 유충기의 whole body로부터 cyclic AMP(CAMP)를 추출하여 농도 변화를 측정하였고 cyclic AMP-dependent protein kinase(PKA)를 부분 정제하여 활성도 변화를 조사하여 CAMP 농도와 PKA 활성도와의 소장관계를 비교하였다 CAMP 농도와 PKA 활성도는 HPLC와 liquid scintillation counter를 이용하여 측정하였다 CAMP 농도는 밤바구미 유충에서 월동전에 0.57 UMlg로 가장 높았고, 월동중에 0. 14 UMIS로 감소하였다가 월동후에 0.29 UMlg로 증가하였다 또한 PKA 활성도는 월동전에 2.56unit/mg로 가장 높았으며, 월동중에 0.62 unit/mg로 감소하다가 월동후에 07 unit/mg로 다시 증가하여 CAMP 농도 변화와 유사한 경향을 나타내었다. 이는 월동전에 휴면에 대비하여 최대의 취식으로 지방체 축적이 가장 많았고, 월동중에는 지방체의 소비가 증대되.기 때문에 감소하였다가, 월동후 휴면 종결과 유충-번데기 탈피를 준비하기 위해 'CAMP 농도와 PKA 활성도는 다시 증가하였다.

  • PDF

Kinetic Study on Dephosphorylation of Myelin Basic Protein by Some Protein Phosphates

  • 황인성;김진한;최명운
    • Bulletin of the Korean Chemical Society
    • /
    • 제18권4호
    • /
    • pp.428-432
    • /
    • 1997
  • The dephosphorylation specificity of protein phosphatase 2A (PP2A), calcineurin (PP2B) and protein phosphatase 2C (PP2C) were studied in vitro using myelin basic protein (MBP) as a model substrate which was fully phosphorylated at multiple sites by protein kinase C (PKC) or cyclic AMP-dependent protein kinase (PKA). In order to determine the site specificity of phosphates in myelin basic protein, the protein was digested with trypsin and the radioactive phosphopeptide fragments were isolated by high performance liquid chromatography (HPLC) on reversed-phase column. Subsequent analysis and/or sequential manual Edman degradation of the purified phosphopeptides revealed that Thr-65 and Ser-115 were most extensively phophorylated by PKA and Ser-55 by PKC. For the dephosphorylation kinetics, the phosphorylated MBP was treated with calcineurin or PP2C with various time intervals and the reaction was terminated by direct tryptic digest. Both Thr-65 and Ser-115 residues were dephosphorylated more rapidly than any other ones by phosphatases. However it can be differentiated further by first-order kinetics that the PP2B dephosphorylated both Thr-65 and Ser-115 with almost same manner, whereas PP2C dephosphorylated somewhat preferentially the Ser-115.

Effects of Staurosporine and Genistein on Superoxide Generation and Degranulation in PMA- or C5a-Activated Neutrophils

  • Ha, Sung-Heon;Lee, Chung-Soo
    • BMB Reports
    • /
    • 제28권3호
    • /
    • pp.210-215
    • /
    • 1995
  • Effects of staurosporine, genistein and pertussis toxin on PMA-induced superoxide generation and degranulation in neutrophils were investigated. Their effects were also examined in C5a-stimulated superoxide generation. PMA-induced superoxide generation was inhibited by staurosporine but was not affected by pertussis toxin. Genistein enhanced the stimulatory effect of PMA in a dose dependent fashion. C5a-induced superoxide generation was inhibited by staurosporine, genistein and pertussis toxin. An NADPH oxidase system of resting neutrophils was activated by PMA, and the stimulatory effect of PMA was inhibited by staurosporine but was not affected genistein and pertussis toxin. The activity of NADPH oxidase in the membrane fraction of PMA-activated neutrophils was not affected by staurosporine and genistein. PMA-induced acid phosphatase release was inhibited by staurosporine and genistein, whereas the effect of pertussis toxin was not detected. These results suggest' that the role of protein tyrosine kinase in neutrophil activation mediated by direct activation of protein kinase C may be different from receptor-mediated activation. The action of protein kinase C on the respiratory burst might be affected by the change of protein tyrosine kinase activity.

  • PDF

The Catalytic Subunit of Protein Kinase A Interacts with Testis-Brain RNA-Binding Protein (TB-RBP)

  • ;길성호
    • 대한의생명과학회지
    • /
    • 제13권4호
    • /
    • pp.305-311
    • /
    • 2007
  • cAMP-dependent protein kinase A (PKA) is the best-characterized protein kinases and has served as a model of the structure and regulation of cAMP-binding protein as well as of protein kinases. To determine the function of PKA in development, we employed the yeast two-hybrid system to screen for catalytic subunit of PKA $(C\alpha)$ interacting partners in a cDNA library from mouse embryo. A Testis-brain RNA-binding protein (TB-RBP), specifically bound to $C\alpha$. This interaction was verified by several biochemical analysis. Our findings indicate that $C\alpha$ can modulate nucleic acid binding proteins of TB-RBP and provide insights into the diverse role of PKA.

  • PDF

바이오칩을 이용한 Protein Kinase C의 활성에 대한 헤스페리딘의 저해 효과 (The Inhibitory Potency of Hesperidin on Protein Kinase C Activity Using a Biochip)

  • 강정애;노종국;최미희;정영진;박상현
    • 방사선산업학회지
    • /
    • 제5권1호
    • /
    • pp.15-20
    • /
    • 2011
  • Protein kinases are the most important drug targets for the treatment of numerous diseases. The involvement of protein kinase C (PKC) in many biological processes such as development, memory, cell differentiation, and proliferation has been demonstrated. PKC is recognized as an important player in carcinogenesis. Thus, a variety of PKC inhibitors have been investigated. Among them, flavonoids have been demonstrated to affect the activity of many mammalian in vitro enzyme systems. The recent investigation was performed to evaluate the inhibitory effects of hesperidin, which is a flavonoid, on the proliferation and carcinogenesis of many cancers. In this study, an efficient kinase assay based on a biochip using radio-phosphorylation was established and performed for an examination of the inhibitory effects of hesperidin on PKC activity at different concentrations of 50, 200, 500 nM. It was found that hesperidin shows inhibitory potency on PKC, and that the biochip can be used to rapidly screen kinase inhibitors resulting in the therapeutic agents.

G292 세포에서 $K^+$통로에 대한 phorbol ester의 효과 (Effect of Phorbol ester on $K^+$channel in an G292 osteoblast-like cell)

  • 김미경;박수병
    • 대한치과교정학회지
    • /
    • 제32권3호
    • /
    • pp.227-234
    • /
    • 2002
  • 본 연구는 조골세포의 특성을 가지고 있는 G292세포주를 이용하여 세포막 이온통로에 대한phorbol ester의 효과를 조사하여 protein kinase C (PCK)의 이온통로에 대한 작용기전을 밝히고자 하였다. Patch clamp 기법을 이용하여 G292 세포에서 cell-attached configuration으로 단일이온통로의 활동을 관찰하고 Phorbol 12, 13-dibutyrate (PDBu)의 효과를 관찰하였다. 안정상태 G292 세포에서 cell-attached 모드로 세포막의 단일이 온통로 활동을 관찰한 결과 45pS의 $K^+$통로가 특징 적으로 우세하였다. 유리 전극 내부에 세포내 액과 세포외 액을 사용하여 전류-전압의 관계를 조사한 결과, 세포내 액을 사용하는 경우에는 역전전압이 5.5mV이었으며 세포외액을 사용하는 경우에는 -27mV이었다. PDBu는 45pS의 이온통로를 10nM이상의 농도에서 이온통로의 열릴 확률을 증가시켰으며 PKC억제제인 staurosporine 10nM에 의하여 차단되는 특성을 보였다. PDBu는 45pS의 이온통로에 작용하여 전류-전압의 관계에서 역전전압을 음의 방향으로 이동시켰으며 동일한 막전압에서 단일이온통로의 전류 크기를 증가시켰다. G292세포에서 PDBu에 의하여 PKC가 활성화되는 것을 western blot으로 확인한 결과 PDBu 0.luM은 세포질에서 세포막으로 PKC translocation을 유의하게 증가시키는 것을 확인하였다. 이상의 결과는 G292세포에서 phorbol ester의 일종인 PDBu가 세포내 PKC를 활성화시켜 45pS의 이온통로를 활성화시키며 이러한 작용의 결과로 세포막전압의 변화가 세포의 기능을 조절할 것으로 사료된다.