Research for the molecular mechanism regulating multu-functresponses mediated via G protein-coupled receptors

G蛋白偶联受体调节多功能反应的分子机制研究

• 批准号: 14370737
• 负责人: NAKAHATA Norimichi
• 金额: $ 7.74万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14370737/
• 关键词: G protein-coupled receptor; thromboxane A_2 receptor; PTH receptor; proteasme; G_<12>; Tctes-1; 4.1G; two hybrid system; two hybrid システム; TP-α; TP-β; PA28γ; α7

Since the ligands to G protein coupled receptors (GPCRs) are utilized for the, treatment of many diseases, it is important to investigate the signal transduction in GPCRs for developing the new effective drugs. Recently, it has been clarified that stimulation of one GPCR results in the multiple responses, although the molecular mechanism has not been clarified. In the present study, we tried to clarify the mechanism in GPCR-mediated multiple signal transduction.To examine the protein directly bound to thromboxane A_2 receptor (TP), yeast two hybrid system was employed. It was found that carboxyl terminal of TP-β, but not TP-α, proteasome activator PA28γ and proteasome subunit α7. Furthermore, an inhibitor of proteasome accelerated, the expression of TP-β, but not TP-α. On the other hand, it has been examined whether TP communicates with G_<12> family G protein using the adenovirus coding the Gα_2 or Gα_<13>. We found that TP clearly communicate G_<12> and G_<13> in addition of Gq. Moreover, we found that C terminal of PTH receptor communicates with Tctex-1 and 4.1G, which show a role of internalization PTH receptor or expression of the receptor in plasma membranes, respectively. Thus, we clarify, the several important regulatory mechanism of GPCR-mediated signal transduction in the present study.

由于G蛋白偶联受体（GPCRs）的配体被广泛应用于多种疾病的治疗，因此研究GPCRs的信号转导机制对于开发新的有效药物具有重要意义。最近，已经阐明了刺激一个GPCR导致多个反应，尽管分子机制尚未阐明。本研究采用酵母双杂交技术，对GPCR介导的多种信号转导机制进行了初步探讨。结果表明，TP-β的羧基端、蛋白酶体激活剂PA 28 γ和蛋白酶体亚基α7的羧基端均被激活，而TP-α的羧基端未被激活。此外，蛋白酶体抑制剂可促进TP-β的表达，但对TP-α无影响。另一方面，用腺病毒载体转染<12>Gα_2或Gα_2基因，检测TP是否与G_家族G蛋白相互作用<13>。我们发现TP除了传递Gq外，还能传递G_<12>和G_<13>。此外，我们还发现PTH受体的C端与Tctex-1和4.1G通讯，这两个蛋白分别参与了PTH受体的内化或表达。因此，我们在本研究中阐明了GPCR介导的信号转导的几个重要调控机制。

项目成果

Minori Saito: "Theonezolide A, a novel marine macrolide, induces drastic shape change in rabbit platelets by reorganization of microtubules"Thrombosis Res.. 108. 133-138 (2003)

Minori Saito：“Theonezolide A，一种新型海洋大环内酯，通过微管重组诱导兔血小板形状发生剧烈变化”Thrombosis Res.. 108. 133-138 (2003)

Haruhisa Kikuchi, Jun Komiya, Yoshinori Saito, Jun-ichi Sekiya, Shigeyoshi Honma, Norimichi Nakahata, Yoshiteru Oshima: "The isolation and synthesis of two novel N-acetylglucosamine derivatives from Dictyostelium cellular slime molds which exhibit neurite

Haruhisa Kikuchi、Jun Komiya、Yoshinori Saito、Jun-ichi Sekiya、Shigeyoshi Honma、Norimichi Nakahata、Yoshiteru Oshima：“从具有神经突的盘基网柄菌细胞粘菌中分离和合成两种新型 N-乙酰氨基葡萄糖衍生物

Masatake Kurita: "Lithium at the"therapeutic"concentration reduces Ca^<2+> response in protein kinase C-down regulated human astrocytoma cells"Eur.J.Pharmacol.. 442. 17-22 (2002)

Masatake Kurita：““治疗”浓度的锂降低了蛋白激酶C下调的人星形细胞瘤细胞中的Ca ^ 2 反应”Eur.J.Pharmacol.. 442. 17-22 (2002)

Norimichi Nakahata, Chikako Tsuchiya, Keigo Nakatani, Yasushi Ohizumi, Satoko Ohkubo: "Baicalein inhibits Raf-1-mediated phosphorylation of MEK-1 in C6 rat glioma cells"Eur.J.Pharmacol.. 461. 1-7 (2003)

Norimichi Nakahata、Chikako Tsuchiya、Keigo Nakatani、Yasushi Ohizumi、Satoko Ohkubo：“黄芩素抑制 C6 大鼠神经胶质瘤细胞中 Raf-1 介导的 MEK-1 磷酸化”Eur.J.Pharmacol.. 461. 1-7 (2003)

Keigo Nakatani: "Inhibition of cyclooxygenase and prostaglandin E_2 synthesis by γ-mangostine. a xanthone derivarive in mangosteen ; in C6 rat glioma cell"Biochem.Pharmacol.. 63. 73-79 (2002)

Keigo Nakatani：“γ-山竹碱对环氧合酶和前列腺素 E_2 合成的抑制。山竹中的氧杂蒽酮衍生物；在 C6 大鼠神经胶质瘤细胞中”Biochem.Pharmacol.. 63. 73-79 (2002)