• BMB Reports
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• 제29권6호
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• pp.535-539
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• 1996

The activation of phospholipase D (PLD) catalyzes hydrolysis of phosphatidylcholine (PC) to phosphatidic acid (PA) and choline in plants as well as animals. To determine the presence of PLD in oat cells, we prepared inside-out plasma membrane and cytosolic fractions from oat tissues. PLD activities in both cytosol and plasma membrane were detected by ion chromatography method. The activity of PLD in plasma membrane was dependent upon $Ca^{2+}$ concentration and was heat stable. To investigate whether G-protein couples to PLD, the effects of $GTP{\gamma}S$ and $GDP{\beta}S$ on the PLD activity were measured. PLD activity was dramatically increased 300~400% in the presence of 50 ${\mu}M$ $GTP{\gamma}S$ but not in the presence of 50 ${\mu}M$ $GDP{\beta}S$. These results indicate that G-protein may be involved in regulation of PLD activity. To identify whether PLD is regulated by red light receptor, phytochrome, we irradiated red, far-red, or red/far-red/red light on oat protoplasts. PLD activity has increased 5-fold and 3-fold by treatment with red light and red/far-red/red light, respectively. In contrast, irradiation with far-red light had little or no effect on PLD activity. These results suggest that phytochrome regulates PLD activity through activation of G-protein in oat cells.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.269.2-269
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• 1995

No Abstract, See Full Text

• Archives of Pharmacal Research
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• 제25권5호
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• pp.675-680
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• 2002

In order to investigate the underlying mechanism of HCI in oesophagitis, the inflammatory response to HCI was observed in RBL-2H3 mast cells. Rat basophilic leukemia (RBL-2H3) cells were used to measure histamine release, arachidonic acid (AA) release, reactive oxygen species (ROS) and peroxynitrite generation induced by HCI. Exogenous HCl increased the level of histamine release and ROS generation in a dose dependent manner, whereas it decreased the spontaneous release of [$^3$H] M and the spontaneous production of peroxynitrite. Mepacrine (10 $\mu$M), oleyloxyethyl phosphorylcholine (10 $\mu$M) and bromoenol lactone (10 $\mu$M) did not affect both the level of histamine release and ROS generation induced by HCI. U73122 (1 $\mu$M), a specific phospholipase C (PLC) inhibitor did not have any influence on level of histamine release and ROS generation. Propranolol (200 $\mu$M), a phospholipase D (PLD) inhibitor, and neomycin (1 mM), a nonspecific PLC and PLD inhibitor, significantly inhibited both histamine release and ROS generation. Diphenyleneiodonium (10 $\mu$M), a NADPH oxidase inhibitor, and tiron (5 mM), an intracellular ROS scavenger significantly inhibited the HCI-induced histamine release and ROS generation. These findings suggest that the inflammatory responses to HCI is related to histamine release and ROS generation, and that the ROS generation by HCI may be involved in histamine release via the PLD pathway in RBL-2H3 cells.

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.196.2-196.2
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• 2000

• Molecules and Cells
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• 제40권11호
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• pp.805-813
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• 2017

The role of phospholipase D (PLD) in cancer development and management has been a major area of interest for researchers. The purpose of this mini-review is to explore PLD and its distinct role during chemotherapy including anti-apoptotic function. PLD is an enzyme that belongs to the phospholipase super family and is found in a broad range of organisms such as viruses, yeast, bacteria, animals, and plants. The function and activity of PLD are widely dependent on and regulated by neurotransmitters, hormones, small monomeric GTPases, and lipids. A growing body of research has shown that PLD activity is significantly increased in cancer tissues and cells, indicating that it plays a critical role in signal transduction, cell proliferation, and anti-apoptotic processes. In addition, recent studies show that PLD is a downstream transcriptional target of proteins that contribute to inflammation and carcinogenesis such as Sp1, $NF{\kappa}B$, TCF4, ATF-2, NFATc2, and EWS-Fli. Thus, compounds that inhibit expression or activity of PLD in cells can be potentially useful in reducing inflammation and sensitizing resistant cancers during chemotherapy.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1998년도 학술발표회
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• pp.31-31
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• 1998

The role of a phosphoinositide-specific phospholipase C, PLC-deltal, in the bradykinin receptor-mediated signaling pathway was investigated using a clone of stably overexpressed PLC-deltal in rat pheochromocytoma (PC12) cells. Stimulation with bradykinin induced significantly higher [Ca$\^$2＋/]i rise in PLC-deltal-overexpressed cells (PC12-D1) than in the wild type (PC12-W) and the vector-transfected (PC12-V) cells.(omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 춘계총회 및 학술대회
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• pp.181.2-181.2
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• 2000

• Bulletin of the Korean Chemical Society
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• 제17권10호
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• pp.905-908
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• 1996

A substrate specificity of cabbage phospholipase D (PLD) was studied using the synthetic phospholipids having different head groups. The phospholipids were synthesized from phosphatidylcholine and appropriate bases by transphosphatidylation of PLD. The bases used were ethanolamine, serine, ethanol and γ-hydroxybutyric acid. The phosphatidic acid, the product of PLD, was separated in TLC and measured densitometrically. The kinetic parameters were estimated for each substrate and the effects of pH, SDS, Ca2+ and other metal ions were examined. Vmax values found were 3.75, 2.36, 5.59, 1.63, 2.30 nmol/min/μg protein for phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylethanol, and phosphatidylburytic acid, respectively. These results indicate a broad specificity of cabbage PLD toward phospholipids with different head groups. Particularly phosphatidylserine was most easily hydrolyzed by PLD and its activity did not depend on Ca2+.

• 생명과학회지
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• 제16권4호
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• pp.691-698
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• 2006

본 연구에서 최근 세포내 신호전달을 매개하는 중요한 효소로써 PLD 동위효소에 대하여, $CoCl_2$가 PLD 동위효소의 활성을 증가시킨다는 사실을 밝혔으며, 중간에 매개되는 단백질로써, PLD1은 p38 MAP kinase, PKA와 $PKC-{\delta}$의 조절을 받고 PLD2는 p38 MAP kinase와 PLC의 조절을 받으므로 그 활성 기전이 각각 다르다는 사실을 확인하였다. 그리고 $CoCl_2$에 의해 생성되는 활성산소 종에 의한 염증상태가 유도될 것이라고 예상하였고 $CoCl_2$가 PLD 동위효소를 매개로 하여 염증상태에서만 특이적으로 발현되고 염증반응을 매개하는 COX-2 단백질에 어떠한 영향을 미칠 것인가를 조사하였다. 결과적으로 $CoCl_2$에 의해 PLD 효소 활성이 증가됨으로써 COX-2의 발현이 증가한다는 것을 발견하였을 뿐만 아니라 COX-2의 발현에 대하여 COX-2 promoter의 활성도 증가한다는 사실을 확인함으로써 전사수준에서의 결과도 이를 뒷받침 해 주고 있었다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 1997년도 국제 심포지움 및 춘계 학술대회
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• pp.65-74
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• 1997

By using guinea pig lung mast cells, this study aimed to examine the effects of Aloe component(NY945) on the mediator releases caused by mast cell activation, and also aimed to assess the effects of NY945 on the mechanism of mediator releases in the mast cell activation. We partially purified mast cells from guinea pig lung tissues by using the enzyme digestion, the rough and the discontinuous density percoll gradient method. Mast cells were sensitized with $IgG_1$ (anti-OA) and challenged with ovalbumin. Histamine was assayed by fluorometric analyzer, leukotrienes by radioimmunoassay The phospholipase D activity was assessed more directly by the production of labeled phosphatidylethanol or phosphatidylbutanol which was produced by phospholipase D-mediated transphosphatidylation in the presence of ethanol or butanol. The amount of mass 1,2-diacylglycerol was measured by the [$^3H$]1,2-diacylgycerol produced when prelabeled with [$^3H$]myristic acid. In the mast cells prelabeled with L-[$^3H$]methyl methionine the phospholipid methylation was assessed by measuring the incorporation of the [$^3H$]methyl moiety into phospholipids. Pretreatment of NY945(10$\mu$g) significantly decreased histamine and leukotrienes releases during mast cell activation. The decrease of histamine release was stronger than that of leukotrienes during mast cell activation. The phospholipase D activity increased by the mast cell activation was decreased by the dose-dependent manner in the pretreatment of NY945. The amount of mass 1,2-diacylglycerol produced by activation of mast cells were decreased in the pretreatment of NY945. NY945 pretreatment strongly inhibited the incorporation of the [$^3H$]methyl moiety into phospholipids. The data suggest that NY945 purified from Aloe inhibits in part an increase of 1,2-diacylglycerol which is produced by activating mast cells with antigen-antibody complexes which is mediated via phosphatidylcholine-phospholipise D and phosphatidylinositole-phospholipise C systems, and then followed by the inhibition of histamine release. Furthermore, NY945 reduces the phosphatidylcholine production by inhibiting the methyltransfsrase I and II, which decrease the conversion of phosphatidylcholine into arachidonic acid and inhibits the production of leukotrines.