• 한국작물학회지
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• 제49권spc1호
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• pp.224-229
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• 2004

• 미생물학회지
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• 제42권4호
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• pp.294-298
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• 2006

Streptomyces somaliensis가 생산하는 phospholipase D (PLD)를 정제하기 위하여 펩티드 항체 결합 면역 친화 크로마토그래피용 칼럼을 개발하였다. 단백질 구조 예측 프로그램과 Streptomyces PLD X-선 결정구조를 참조하여, S. somaliensis PLD의 1차 구조로부터 항원특성이 높고. 표면에 위치하는 것으로 예상된 5종류의 펩티드들을 epitope로 선정한 뒤, 이에 대한 항체로 면역친화 크로마토그래피용 칼럼을 제작하였다. 배양 농축액을 칼럼에 통과시켜 정제한 활성 분획을 SDS-PAGE 및 Western blot 결과, 칼럼 종류에 따라 순수한 PLD또는 35 kDa의 단백질 불순물만을 포함하는 PLD 정제 분획을 보여 면역친화 칼럼의 높은 항원결합 특이성을 보여주었다. 그러나 수용액상에서 PLD 자체의 구조적 불안정성 때문에 정제 후 PLD의 특이적 활성 및 정제 수율은 낮았다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2000년도 춘계학술대회
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• pp.15-16
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• 2000

Transient forebrain ischemia results in delayed neuronal death in the CA1 region of the hippocampus after injury, which is, at least in part, a consequence of excessive generation of reactive oxygen species. Previous in vitro studies using cell cultures or brain slices have demonstrated that phospholipase D (PLD) in the nervous system is involved in the signaling mechanism in response to a variety of agonists. Several recent studies have shown that reactive oxygen species stimulate phospholipase D (PLD) activity in several kinds of cells. Therefore, this raises the possibility that PLD activity is enhanced in the ischemic brain. Meanwhile, osteopontin (OPN) was initially identified as a sialoglycoprotein in bone, but has since been found in various tissues. Although not much is known about its function, OPN seems to play an important role in inflammation and tissue repair. Recently, it was reported that OPN was upregulated in the activated microglia after focal brain ischemia, suggesting that OPN might play a role in wound healing after a focal stroke.

• 생명과학회지
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• 제13권6호
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• pp.924-932
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• 2003

녹차의 주성분인 에피갈로 갈레이트 (EGCG)는 건강에 이로운 효과로 나타내고 있는것으로 알려져 있어 많은 주목을 받고 있는 실정이다 본 연구에서는 처음으로 EGCG가, U87사람의 교세포에서 포스포리파제 D의 효소활성을 증가시킨다는 사실을 규명하였다. EGCG에 의한 포스포리파제 D의 활성화는 포스포리파제 C효소의 특이적인 억제제와 지질분해효소 활성이 억제제 포스포리파제 \gama1$의 변이체를 이용하여 실험한 결과 세포내 칼슘에 의존적인 양상을 보였주었다. 이러한 포스포리파제 D의 활성화는 아마도 칼슘 의존성 단백질 키나아제 II (CaM kinase II)를 통하여 일어나는것으로 여겨진다. 흥미롭게도, EGCG는 포스포리파제 \gama1$를 세포질에서 세포막으로의 이동을 유도하였으며, 포스포리파제 \gama1$와 PLD1의 결합을 유도하였음을 관찰하였다. 이상의 결과들을 종합하여 볼 때, EGCG가 사람의 교세포에서 포스포리파제 \gama1$-칼슘-CaM kinase II의 신호전달 경로를 통하여 포스포리파제 D의 활성을 유도하는 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.71-76
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• 2002

Soil samples were screened for actinomycete strains capable of producing phospholipase D, and a strain, Streptomyces sp. YU100, showing a high transphosphatidylation activity was isolated. This strain secreted phospholipase D in a culture broth after 12 h of cultivation, and its productivity continued to increase for 36 h of fermentation. In addition, its transphosphatidylation rate of phosphatidylcholine to phosphatidylserine was almost $68\%$ within 1 h. The morphological and chemotaxonomical characteristics showed that this strain could be classified as a number of the Streptomycetaceae family, particularly due to the spiral form of its spore chain consisting of 60-70 smooth spores $(0.75{\times}1.0{\mu}m$) on an aerial mycelium, FA-2c type of fatty acid profile in the cell wall, and LL-DAP component in the cell wall peptidoglycan. A phylogenetic analysis of the 16S rDNA provided a clue that the strain YU100 was actually a member of the genus Streptomyces, because the determined sequence exhibited a higher homology with Streptomyes sp. ASB27, S. peucetius JCM9920, and S. griseus ATCC10137. A dendrogram based on the 16S rDNA sequences also showed a phylogenetic relationship between the strain YU100 and these strains. However, the strain YU100 has not yet been assigned to a particular species, because of absence of any other classified species with a high matching score.

• 대한의생명과학회지
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• 제15권4호
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• pp.287-293
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• 2009

Phospholipase D (PLD) is an enzyme hydrolyzing phosphatidylcholine to phosphatidic acid (PA) and choline. We investigated the involvement of PLD1 in the uptake of norepinephrine (NE) in PC12 cells, pheochromocytoma cells. NE uptake was specific in PC12 cells because nomifensine, a specific blocker of NE transporter, blocked NE uptake. Inhibition of PLD function in PC12 cells by the treatment of butanol suppressed the NE uptake. In contrast, overexpression of PLD1 in PC12 cells increased NE uptake efficiently. These results suggest that PLD activity is involved in NE uptake. We explored the action mechanism of PLD in NE uptake. PA phosphatase inhibitor, propranolol, blocks the formation of PKC activator diacylglycerol from PA. Propranolol treatment to PC12 cells blocked dramatically the uptake of NE. Specific PKC inhibitors, GF109203X and Ro31-8220, blocked NE uptake. Taken together, we suggest for the first time that PLD1 activity is involved in NE uptake via the activation of PKC.

• Journal of Acupuncture Research
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• 제18권1호
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• pp.129-145
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• 2001

Objectives : To characterize the antitumorigenic potential of three representative bee venom components, Melittin, Apamin, and Phospholipase A2, their effects on cell proliferation and apotosis of the human melanoma cell line SK-MEL-2 were analyzed using molecular biological approaches. Methodes & Results : To determine the doses of the drugs that do not induce cytotoxic damage to this cell line, cell viability was examined by MTT assay. While SK-MEL-2 cells treated with 0.5 - 2.0㎍/㎖ of each drug showed no recognizable cytotoxic effect, marked reductions of cell viability were detected at concentrations over 5.0㎍/㎖. [3H]thymidine incorporation assay for cell proliferation demonstrated that DNA replication of SK-MEL-2 cells is inhibited by Apamin and Phospholipase A2 in a dose-dependent manner. Consistent with this result, the cells were accumulated at the G1 phase of the cell cycle after treatment with Apamin and Phospholipase A2, whereas no detectable change in cell proliferation was identified by Melittin treatment. In addition, tryphan blue exclusion and flow cytometric analyses showed that all of these drugs can trigger apoptotic cell death of SK-MEL-2, suggesting that Melittin, Apamin, and Phospholipase A2 have antitumorigenic potential through the suppression of cell growth and/or induction of apoptosis. Qantitative RT-PCR analysis revealed that Apamin and Phospholipase A2 inhibit expression of growth-promoting genes such as c-Jun, c-Fos, and Cyciin D1. Furthermore, Phospholipase A2 induced tumor suppressors p53 and p21/Wafl. In addition, all three drugs were found to activate expression of a representative apoptosis-inducing gene Bax while expression of apoptosis-suppressing Bcl-2 and Bcl-XL genes was not changed. Taken together, this study strongly suggests that Metittin, Apamin, and Phosphalipase A2 may have antitumorigenic activities, which are associated with its growth-inhibiting and/or apoptosis-inducing potentials.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.107-108
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• 2003

The epidermal growth factor (EGF) is an important signaling ligand for the mitogenesis of many cells. The EGF receptors use signaling molecule multicomplexes and dynamic protein networks for the transmission and amplification of the signals as well as for the regulation of the cellular responses. EGF signaling has been reported to be enhanced in various tumors by the overexpressed EGF receptor and/or the mediators such as phospholipase C-$\gamma$1(PLC$\gamma$1). (omitted)

• 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)

• 식물조직배양학회지
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• 제27권5호
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• pp.375-377
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• 2000

It is now generally accepted that a phosphoinositide cycle is involved in the transduction of a variety of signals in plant cells. In animal cells, the hydrolysis of phosphatidyl-4,5-bisphosphate catalysed by phosphatidylinositol - specific phospholipase C yields to D-myo-inositol - 1,4,5-trisphosphate and diacylglycerol, which are well known second messengers. The binding of InsP$_3$to a receptor located on the endoplasmic reticulum triggers a calcium release from the endoplasmic reticulum. We have detected and partially characterised key components of phosphoinositide signaling. First, tobacco microsomal fraction and plasma membrane PI-PLC. Consecutively, using a radioligand binding assay we have identified a $Ca^{2+}$ -dependent high affinity InsP$_3$binding site in microsomal membrane fraction vesicle preparation and then we have measured inositol-1,4,5-trisphosphate induced calcium release from tobacco microsomal fraction. These findings suggest that phosphoinositide signaling system is present and operates in the tobacco suspension culture.e.