Function of membrane glycoprotein V as a negative regulator for platelet activation.

膜糖蛋白 V 作为血小板活化负调节因子的功能。

• 批准号: 12670990
• 负责人: FUJIMURA Kingo
• 金额: $ 1.98万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12670990/
• 关键词: platelets; GPV; von Willebrand factor receptor; GPIb-IX complex; Two hybrid system; filamin; FBLP-1; cytoplasmic domain; トロンビン; 巨核球

In order to determine the function of membrane glycoprotein V (GPV) on platelet activation, proteins which bind to the cytoplasmic domain of GPV were identified by yeast two hybrid screening. Since the cytoplasmic tail of murine GPV cDNA and murine megakaryocytic cell lines. One positive clone was identified. In addition, proteins that bind to filamins were also identified by years two hybrid screening since filamin was known as a binding protein to the von Willebrand factor receptor GPIb-V-IX complex. One clone was a novel cDNA, which encoded 375 amino acids and 45kDa protein. Deduced amino acid sequence showed that it contained a proline-rich domain at its N-terminal half and two LIM domains at C-terminus. We therefore, named it as FBLP-1 (Filamin Binding LIM Protein-1). Subcellular localization analysis showed that FBLP-1 co-localized with stress fibers, which stretched from focal adhesions. The cells, which over-expressed FBLP-1, spread more effectively than the cells which did not express FBLP-1, suggesting that FBLP-1 plays a significant role on platelet adhesion. Further investigation of the associated protein would clarify the function of platelet GPV.

为了确定膜糖蛋白V (GPV)对血小板活化的功能，通过酵母二杂交筛选鉴定了与GPV胞质结构域结合的蛋白质。自鼠GPV cDNA和鼠巨核细胞系的胞浆尾。鉴定出 1 个阳性克隆。此外，由于细丝蛋白被认为是冯维勒布兰德因子受体 GPIb-V-IX 复合物的结合蛋白，因此通过两年的混合筛选也鉴定出了与细丝蛋白结合的蛋白质。其中一个克隆是一种新型 cDNA，编码 375 个氨基酸和 45kDa 蛋白质。推导的氨基酸序列显示，其N端半部含有富含脯氨酸的结构域，C端含有两个LIM结构域。因此，我们将其命名为 FBLP-1（Filamin Binding LIM Protein-1）。亚细胞定位分析表明 FBLP-1 与从粘着斑延伸的应力纤维共定位。过表达FBLP-1的细胞比不表达FBLP-1的细胞更有效地扩散，表明FBLP-1在血小板粘附中发挥重要作用。对相关蛋白的进一步研究将阐明血小板 GPV 的功能。

项目成果

Fujimoto, T.T., et al.: "Involvement of Fcγ receptor polymorphism in the therapeutic response of idiopathic thrombocvtopenic purpura."Br. J. Haematol.. 115. 125-130 (2001)

Fujimoto, T.T. 等人：“Fcγ 受体多态性参与特发性血小板减少性紫癜的治疗反应。Br. J. Haematol.. 115. 125-130 (2001)

Fujii, T., et al.: "A new approach to detect reticulated platelets stained with thiazole orange in thrombocytopenic patients."Thromb. Res.. 97. 431-440 (2000)

Fujii, T. 等人：“一种检测血小板减少症患者中用噻唑橙染色的网织血小板的新方法。”血栓。

藤元 貴啓: "血小板産生異常と巨大血小板.細胞の形態形成の基本メカニズム"金芳堂,京都. 163-175 (2001)

Takahiro Fujimoto：“血小板生成异常和巨型血小板。细胞形态发生的基本机制”Kinhodo，Kyoto 163-175（2001）。

Fujii T, et al: "A new approach to detct reticulated platelets stained with thiazole orange in thrombocytopenic patients"Thromb. Res. 97. 431-440 (2000)

Fujii T 等人：“一种在血小板减少症患者中检测用噻唑橙染色的网状血小板的新方法”血栓。

Fujimoto, T.T., et al.: "Novel alternatively spliced form of β_3-endonexin"Thromb. Res.. 105. 63-70 (2002)

Fujimoto, T.T., et al.：“β_3-endonexin 的新型选择性剪接形式”Res.. 105. 63-70 (2002)