• 생약학회지
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• 제30권3호
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• pp.280-283
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• 1999

Using the bioassay-guided fractionation and isolation technique, two $PLC{\gamma}1$ inhibitors were isolated from the sarcotestas of Ginkgo biloba (Ginkgoaceae). The structures of these compounds were identified as (3R)-(-)-8-hydroxy-3-(6'-pentadecenyl)3,4-dihydroisocoumarin (1) and 3-heptadecen-2-one (2) by UV, IR, MS, $^1H-NMR$, $^{13}C-NMR$ and $^1H-^{13}C\;COSY$. Isolate compounds 1 and 2 have not been reported previously from the sarcotestas of G. biloba and Ginkgoaceae, respectively. In addtion, these compounds showed significant $PLC{\gamma}1$ inhibitory effects with the $IC_{50}$ of the 9.7 (1) and $25.6\;{\mu}M\;(2)$.

• BMB Reports
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• 제40권6호
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• pp.888-894
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• 2007

Src homology (SH) domains of phospholipase C-$\gamma1$ (PLC-$\gamma1$) impair NGF-mediated PC12 cells differentiation. However, whether the enzymatic activity is also implicated in this process remains elusive. Here, we report that the enzymatic activity of phospholipase C-$\gamma1$ (PLC-$\gamma1$) is at least partially involved to the blockage of neuronal differentiation via an abrogation of MAPK activation, as well as sustained Akt activation. By contrast, Overexpression of WT-PLC-$\gamma1$ exhibited sustained NGF-induced MAPK activation, and triggered transient Akt activation resulting in profound inhibition of neurite outgrowth. However, lipase-inactive mutant (LIM) PLC-$\gamma1$ cells fail to suppress neurite outgrowth, although it contains intact SH domains, specifically enhancing the expression of cyclin D1 and p21 proteins, which regulate the function of retinoblastoma Rb protein. These observations show that the lipase inactive mutant of PLC-$\gamma1$ does not alter NGF-induced neuronal differentiation via enzymatic inability and the modulation of cell cycle regulatory proteins independent on SH3 domain.

• BMB Reports
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• 제35권5호
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• pp.508-512
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• 2002

Phospholipase C-gamma-2 ($PLC{\gamma}2$) activation is a key signaling event for many cell functions. In order to delineate the pathways that lead to $PLC{\gamma}2$ activation, we devised a quick method for obtaining sufficient $PLC{\gamma}2$. We obtained the full-length cDNA for human $PLC{\gamma}2$ and expressed it in E. coli using the expression vector pT5T. To enhance the protein expression, tandem AGG-AGG arginine codons at the amino acid positions 1204-1205 were replaced by CGG-CGG arginine codons. The protein expression was detected in a Western blot analysis by both anti-$PLC{\gamma}2$ antibodies and the antibodies that are raised against the tripeptide epitope (Glu-Glu-Phe) tag that are genetically-engineered to its carboxyl terminal. Crude lysates that were prepared from bacteria that express $PLC{\gamma}2$ were found to catalyze the hydrolysis of phosphatidylinositol 4,5 bisphosphate. Similar to previous reports on $PLC{\gamma}2$ that is isolated from mammalian tissue, the recombinant enzyme was $Ca^{2+}$ dependent with optimal activity at 1-10 uM $Ca^{2+}$.

• 대한의생명과학회지
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• 제12권4호
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• pp.419-425
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• 2006

Phospholipase $C-{\gamma}1\;(PLC-{\gamma}1)$ is an important signaling molecule for cell proliferation and differentiation. $PLC-{\gamma}1$ contains two pleckstrin homology (PH) domains, which are responsible for protein-protein interaction and protein-lipid interaction. $PLC-{\gamma}1$ also has two Src homology (SH)2 domains and a SH3 domain, which are responsible for protein- protein interaction. To identity proteins that specifically binds to PH domain of $PLC-{\gamma}1$, we prepared and incubated the glutathione S-transferase(GST)-fused PH domains of $PLC-{\gamma}1$ with COS7 cell lysate. We found that 90 kDa protein specifically binds to PH domain of $PLC-{\gamma}1$. By matrix-assisted laser desorption ionization time of flight-mass spectrometry, the 90 kDa protein revealed to be heat shock protein (Hsp) $90{\beta}$. Hsp $90{\beta}$ is a molecular chaperone that stabilizes and facilitates the folding of proteins that are involved in cell signaling, including receptors for steroids hormones and a variety of protein kinases. To know whether Hsp $90{\beta}$ affects on $PLC-{\gamma}1$ activity, we performed $PIP_2$ hydrolyzing activity of $PLC-{\gamma}1$ in the presence of purified Hsp $90{\beta}$ in vitro. Our results show that the Hsp $90{\beta}$ dose-dependently inhibits the enzymatic activity of $PLC-{\gamma}1$ and further suggest that Hsp $90{\beta}$ regulates cell growth and differentiation via regulation of $PLC-{\gamma}1$ activity.

• 대한후두음성언어의학회지
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• 제12권2호
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• pp.126-132
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• 2001

Background and Objectives : Signal traduction through phospholipase C(PLC) participate in the regulation of cell growth and differentiation. Growth factors bind to their receptors and thereby induce tyrosine phophorylation of the phospholipase C-${\gamma}$1(PLC-${\gamma}$1). PLC-${\gamma}$1 is a substrate for several receptor tyrosine kinases and its catalytic activity is increased by tyrosine phosphorylation. Tyrosine kinase phosphorylation of PLC-${\gamma}$1 stimulates PLC activation and cell proliferation. However the signal transduction pathway and the significance of PLC in injured recurrent laryngeal nerve regeneration is unknown. Therefore after we obtained fuctionally recovered rats using PEMF in this study, we attempt to provide some evidence that PLC plays a role in nerve regeneration itself and regeneration related to PEMF through the analysis of the difference between fucntional recovery group and non-recovery group in the recurrent laryngeal nerve. Materials and Method : Using 32 healthy male Sprague-Dawley rats, transections and primary anastomosis were performed on their left recurrent laryngeal nerves. Rats were then randomly assigned to 2 groups. The experimental group(n=16) received PEMS by placing them in custom cages equipped with Helm-holz coils(3hr/day, 5days/wk, for 12wk). The control group(n=16) were handled the same way as the experimental group, except that they did not receive PEMS. Laryngo-videoendoscopy was performed before and after surgery and followed up weekly. Laryngeal EMG was obtained in both PCA and TA muscles. Immunohistochemisty staining and Western blotting analysis using monoclonal antibody was performed to detect PLC-${\gamma}$1 in recurrent laryngeal nerve and nodose ganglion. Results : 10 rats(71%) in experimental group and 4 rats(38%) in the control group showed recovery of vocal fold motion. Functionally-recoverd rats show PLC-${\gamma}$1 positive cells in neuron and ganglion cells after 12 weeks from nerve injury. Conclusion : This study shows that PLC1-${\gamma}$ involved in singnal trasduction pathway in functinal recovery of injured recurrent laryngeal nerve and PEMF enhance the functional recovery by effect on this molecule.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.63-63
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• 1993

Phospoinositide-specific phospholipase C (PLC)는 세포막의 phosphoinositide를 분해하여 inositol phosphates와 diacylglycerol을 전달하는데 핵심적인 효소이다. PLC는 분자량과 1차구조의 비교에 의하여 type (PLC-$\beta$, ${\gamma}$, $\delta$)로 구분되며, 각 type마다 2-4종의 subtype이 존재하고 PLC isozyme들에 대한 현재가지의 각종 신호 전달 및 조절에 대한 연구를 종합하면: (1) PLC-$\beta$ type은 G-protein과 연결되어 신호를 전달받고, (2) PLC-${\gamma}$ type은growth factor receptor tyrosine kinase에 의하여 인산화 되어 활성화됨으로, 세포의 성장 신호를 전달하며. (3) PLC-$\delta$ type에 대한 신호 전달이나 조절은 밝혀지지 않고 있다.

• 생명과학회지
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• 제13권6호
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• pp.849-855
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• 2003

NO는 태반의 영양모세포의 증식에서 중요한 신호전달인자로서 작용을 한다. 본 연구에서는 choriocarcinoma 세포주인 BeWo 세포에서 NO에 의한 세포의 증식에서PLC의 관련성을 조사하였다. 세포 내 NO 생성을 자연적으로 유발하는 약물인 SNP를 단독으로 처리하였을 때 BeWo 세포에서 $［^3H］$thymidine의 축적 양이 현저히 증가하였는데 이러한 결과는 NO가 BeWo 세포의 증식을 촉진한다는 것을 보여주고 있다. NO에 의한 BeWo 세포의 증식은 PLC의 억제제인 U73122에 의하여 현저히 감소하였다. BeWo 세포에 SNP를 10분간 처리하였을 때 ERK1/2의 인산화가 증가되는 것을 Western blot으로 확인하였다. 이들 인산화는 U73122에 의하여 아무런 영향을 받지 않았다. $PLC\gamma_1$과 $PLC\gamma_2$에 대한 특이 항체를 이용한 면역침전을 시행한 후 phosphotyrosine에 대한 항체인 PY로 Western blotting을 시행하였을 때 PLC${\gamma}$$_1$은 SNP에 의하여 tyrosine 잔기의 인산화가 이루어졌으나 $PLC\gamma_2$는 인산화가 되지 않았다. SNP에 의한 $PLC\gamma_1$의 인산화는 genistein이나 PD98059를 전 처리하였을 때 억제되었다. 따라서, NO에 의한$PLC\gamma_1$의 tyrosine 인산화는 ERK의 활성을 통하여 일어난다는 것을 알 수 있다 이상의 결과들은 BeWo세포에서 NO는 세포증식을 촉진하며 ERK와 $PLC\gamma_1$의 활성화를 통하여 일어난다는 사실을 제시하고 있다.

• 한국발생생물학회지:발생과생식
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• 제2권1호
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• pp.9-20
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• 1998

Phospholipase C (PLC)는 다양한 세포주에서 세포내 신호전달에 중요한 역할을 한다고 알려져 있으나, 생쥐 난자성숙 과정과 착성전 배아발생 과정에서 PLC의 역할과 발현은 아직 연구된 바 없다. 본 연구에서는 난자성숙과 착상전 배아발생 과정에서 생쥐의 PLC \beta 1과 \gamma 1의 유전자 발현을 조사하기 위하여 한 개의 난자 혹은 배아에서 추출된 total RNA를 사용하여 경쟁적 RT-PCR 방법으로 mRNA를 정량하였다. PLC \gamma 1의 유전자 발현을 조사하기 위하여 한 개의 난자 혹은 배아에서 추출된 total RNA를 사용하여 경쟁적 RT-PCR 방법으로 mRNA를 정량하였다. PLC \gamma 1의 유전자는 전혀 발현하지 않았다. 수정후 PLC \betta 1과 \gamma 1의 유전자 발현은 상실기 배아에서 증가하기 시작하여 포배기 배아에서는 현저히 증가하였다. 난자성숙과 착상전 배아발생 과정에서 protein kinase C(PKC) 신호전달체게에 의한 PLC의 역할을 조사하기 위하여 PKC의 억제제인 sphingosin, PKC의 촉진제인 $diC_{8}$, 그리고 PLC의 억제제인 U73122의 효과를 조사하였다. Spihingosine은 처리후 1시간 이내에 대조군에 비해 20% 정도의 난자성숙을 촉지하였으나 U73122는 유효한 효과를 보이지 않았다. U73122는 상실기 배아의 compaction을 억제하였으나 $diC_{8}$에 의하여 부분적으로 극복되었다. 이상의 결과는 PLC \beta 1과 \gamma 1 유전자가 생쥐의 착상전 발생단계에서 특이젖으로 발현하고 있으며, 난자성숙과 착상전 초기배아에서 PKC-PLC 신호전달체계가 관여하고 있으리라 사료된다.

• 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)

• Biomolecules & Therapeutics
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• 제20권6호
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• pp.526-531
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• 2012

During our on-going studies to identify bioactive compounds in medicinal herbs, we found that saucerneol F (SF), a naturally occurring sesquilignan isolated from Saururus chinensis (S. chinensis), showed in vitro anti-inflammatory activity. In this study, we examined the effects of SF on the generation of 5-lipoxygenase (5-LO) dependent leukotriene $C_4$ ($LTC_4$), cyclooxygenase-2 (COX-2) dependent prostaglandin $D_2$ ($PGD_2$), and on phospholipase $C{\gamma}1$ ($PLC{\gamma}1$)-mediated degranulation in SCF-induced mouse bone marrow-derived mast cells (BMMCs). SF inhibited eicosanoid ($PGD_2$ and $LTC_4$) generation and degranulation dose-dependently. To identify the molecular mechanisms underlying the inhibition of eicosanoid generation and degranulation by SF, we examined the effects of SF on the phosphorylation of $PLC{\gamma}1$, intracellular $Ca^{2+}$ influx, the translocation of cytosolic phospholipase $A_2$ ($cPLA_2$) and 5-LO, and on the phosphorylation of MAP kinases (MAPKs). SF was found to reduce intracellular $Ca^{2+}$ influx by inhibiting $PLC{\gamma}1$ phosphorylation and suppressing the nuclear translocations of $cPLA_2$ and 5-LO via the phosphorylations of MAPKs, including extracellular signal-regulated protein kinase-1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38. Taken together, these results suggest that SF may be useful for regulating mast cell-mediated inflammatory responses by inhibiting degranulation and eicosanoid generation.