Regulation of peptides secretion by orphan G protein coupled receptor

孤儿G蛋白偶联受体对肽分泌的调节

• 批准号: 18390024
• 负责人: HIRASAWA Akira
• 金额: $ 10.92万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18390024/
• 关键词: Proteome; signal transduction; Microarray; pharmaceutical sciences; genome; オーファン受容体; 脂肪酸; 分泌; ペプチド; 脂肪酸受容体; 質量分析

Agonist activation of a G protein-coupled receptor (GPCR) results in the redistribution of the receptor protein away from the cell surface into internal cellular compartments through a process of endocytosis known as internalization. We examined whether the ligand-mediated internalization of a GPCR can be exploited for pharmacological evaluations. We acquired fluorescent images of cells expressing GFP-labeled GPCRs and evaluated the ligand-mediated internalization quantitatively by image processing. The rank order of receptor internalization potency for a variety of agonists and antagonists specific to each receptor corresponded well with that previously observed in ligand binding studies. In addition to chemical ligand-induced internalization, this cell-based fluorescence imaging system successfully monitored the internalization of the proton-sensing GPCR TDAG8, and that of the free fatty acid-sensitive GPCR GPR120. The results show. That monitoring receptor internalization can be a u … More seful approach for pharmacological characterization of GPCRs and in fishing for ligands of orphan GPCRs.We have recently found that GPR120, which is abundantly expressed in intestine, functions as a receptor for unsaturated long-chain free fatty acids (FFAs) and that GPR120 stimulation promotes the secretion of glucagons-like peptide-1 (GLP-1) in the mouse. The ingestion of fat induces secretion of the gut peptide hormone cholecystokinin (CCK). In this study, we examined whether these FFA receptors mediate-lipid-induced CCK and other peptide release in the mouse. We first observed that intra-gastric administration of long-chain FFAs increased plasma CCK levels. Using mouse enteroendocrine STC-1 cells as a model system, we further studied the mechanism of this FFA induced CCK secretion_ Long-chain FFAs promoted CCK secretion from STC-1 cells, which was abolished either by removal of extracellular Ca2+or by the L-type Ca^<2+>channel blacker nicardipine. Furthermore, this FFA-induced CCK secretion was specifically inhibited by transfection of GPR120-specific, but not GPR40-specific, short hairpin RNA. These results indicate that long-chain FFAs induce CCK secretion through GPR120-coupled Ca^<2+>signaling. Less

G蛋白偶联受体（GPCR）的激动剂活化导致受体蛋白通过称为内化的内吞作用过程远离细胞表面重新分布到内部细胞区室中。我们研究了配体介导的GPCR内化是否可以用于药理学评价。我们获得了表达GFP标记的GPCR的细胞的荧光图像，并通过图像处理定量评估配体介导的内化。针对每种受体的多种特异性激动剂和拮抗剂的受体内化效力的排序与之前在配体结合研究中观察到的一致。除了化学配体诱导的内化之外，这种基于细胞的荧光成像系统成功地监测了质子敏感GPCR TDAG 8和游离脂肪酸敏感GPCR GPR 120的内化。结果显示。监测受体的内化可能是一种有用的方法， ...更多信息 我们最近发现，GPR 120，这是在肠道中大量表达，作为一个不饱和长链游离脂肪酸（FFA）的受体，GPR 120刺激促进分泌胰高血糖素样肽-1（GLP-1）在小鼠中发挥作用。脂肪的摄入诱导肠肽激素胆囊收缩素（CCK）的分泌。在这项研究中，我们研究了这些FFA受体是否介导脂质诱导的CCK和其他肽在小鼠中的释放。我们首先观察到，胃内给予长链游离脂肪酸增加血浆CCK水平。以小鼠肠内分泌STC-1细胞为模型系统，进一步研究了FFA诱导CCK分泌的机制：长链FFA促进STC-1细胞分泌CCK，但这一作用可被细胞外Ca ~（2+）清除或L型Ca^<2+>通道阻断剂尼卡地平所阻断。此外，这种FFA诱导的CCK分泌特异性抑制转染GPR 120特异性，但不是GPR 40特异性，短发夹RNA。这些结果表明长链游离脂肪酸通过GPR 120偶联的Ca^<2+>信号传导诱导CCK分泌。少

项目成果

In silicoリガンド予測法によるGPCR新規リガンドの探索とその評価

利用计算机配体预测方法寻找新的GPCR配体及其评价

• 发表时间: 2006
• 作者: Hirasawa;A;原 貴史
• 通讯作者: 原 貴史

Difference in Ca2+Oscillation-Inducing Actinvity and Nuclear Translocation Ability of PLCZ1, an Egg-Activating Sperm Factor Candidate, Between Mouse, Rat, Human, and Medaka Fish.

PLCZ1（一种卵子激活精子因子候选物）在小鼠、大鼠、人类和青鳉鱼之间 Ca2 振荡诱导活性和核转位能力的差异。

• 发表时间: 2008
• 期刊: Biol Reprod. (In press)
• 作者: Tanaka T.;Ito M.
• 通讯作者: Ito M.

Ligand identification and functional analysis for orphan GPCR GPR120

• 发表时间: 2005
• 期刊: Yakugaku Zasshi-journal of The Pharmaceutical Society of Japan
• 影响因子: 0.3
• 作者: A. Hirasawa;G. Tsujimoto

Difference in Ca2+ oscillation-inducing activity and nuclear translocation ability of PLCZ1, an egg-activating sperm factor candidate, between mouse, rat, human, and medaka fish

• DOI: 10.1095/biolreprod.108.067801
• 发表时间: 2008-06-01
• 期刊: BIOLOGY OF REPRODUCTION
• 影响因子: 3.6
• 作者: Ito, Masahiko;Shikano, Tomohide;Miyazaki, Shunichi
• 通讯作者: Miyazaki, Shunichi

Immunological tolerance-related genes in a spontaneous tolerant model of rat liver transplantation explored by suppression subtractive hybridization.

通过抑制消减杂交探索大鼠肝移植自发耐受模型中的免疫耐受相关基因。

• 发表时间: 2008
• 期刊: Cell Transplant. 17
• 作者: Tanaka T.;Ito M.;Kazuhiro Katayama;Zhang H.
• 通讯作者: Zhang H.