Unity and diversity of ion transport mechanisms and regulation of Na+/H+ antiporters

离子转运机制的统一性和多样性以及Na /H反向转运蛋白的调节

• 批准号: 13142207
• 负责人: KANAZAWA Hiroshi
• 金额: $ 54.21万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13142207/
• 关键词: intracellular ion homeostasis; Na+; H+ exchangers; pH regulation; salinity resistance; active transporters; molecular structure of membrane proteins; intracellular localization of membrane proteins; molecular biological approach; 細胞内イオン恒常性; 膜蛋白質

Regulation of intracellular pH, Na^+ concentration, and osmolality are the most important factors for cell survival. These regulations are performed mainly by Na^+/H^+ exchangers named NhaA or NHE on the cytoplasmic as well as endocytic membranes. In this project we aimed to elucidate molecular structure-function relationship and functional regulation of these antiporters including intracellular localization of these molecules for these molecules from bacteria, yeast and mammalian cells. As a result, following achievement was performed. (1) For H pylori NhaA membrane integral domains essential for the ion transport were identified. Further the residues important or essential for Na^+ and H^+ binding were estimated and their hydrophobic environment within the membranes were elucidated. A new detection system of conformational change of NhaA during the ion transport was set up. (2) For yeast Nhalp essential or important residues for the ion transport were identified. Function of the hydrophilic C terminal half domain which seems to be similar to the mammalian NHE were analyzed. A membrane jaxta-positional 16 amino acid residues and its flanking 38 amino acid residues were found to be essential for destination of Nhalp to the cytoplasmic membrane, and binding Cos3p, a noble protein capable enhancing the ion exchange, respectively. (3) For mammalian NHE, we identified two new isoforms, NHE8 and 9. The isoforms NHE 6 to 9 were found to be in the membranes of various endocytic vesicles and function as K+/H+ antipoter rather than Na^+/H^+ antiporter, leading to regulate pH within endocytic vesicles. CHP capable binding NHE1-5 found by us was found to bind other proteins, DRAK2 (apoptotic protein kinase) and KIFIB□ (Kinesin isoform). The present findings will contribute to understand the function and structure relation ship and the regulations of these proteins as well as for elucidating diversity and unity of Na+/H+ antoporters among various organs and species.

细胞内pH，Na^+浓度和渗透压的调节是细胞存活的最重要因素。这些法规主要由Na^+/h^+交换器在细胞质和内吞机制上称为NHAA或NHE。在这个项目中，我们旨在阐明这些抗虫的分子结构功能关系和功能调节，包括这些分子对细菌，酵母和哺乳动物细胞的这些分子的细胞内定位。结果，完成成就后。 （1）对于H幽门螺杆菌NHAA膜积分结构域，确定了离子转运必不可少的。此外，估计了对Na^+和H^+结合至关重要的残留物，并阐明了它们在膜内的疏水环境。在离子运输过程中建立了一种新的NHAA会议变化的检测系统。 （2）确定了离子运输的酵母NHALP必需物质或重要残差。分析了与哺乳动物NHE相似的亲水C末端半结构域的功能。发现膜JAXTA固定16氨基酸保留及其侧翼38氨基酸保留对于NHALP目的地至细胞质膜至关重要，并且结合COS3P（分别能够增强离子交换的贵族蛋白）。 （3）对于哺乳动物NHE，我们发现了两种新的同工型NHE8和9。发现同工型NHE 6至9位于各种内吞蔬菜的膜上，并且功能为K+/H+抗植物，而不是Na^+/H^+/H^+抗管剂，从而调节了内囊蔬菜的pH。发现美国发现的有能力结合的NHE1-5可以结合其他蛋白质Drak2（凋亡蛋白激酶）和Kifib□（驱动蛋白同工型）。目前的发现将有助于了解这些蛋白质的功能和结构关系船以及这些蛋白质的法规，以及阐明各种器官和物种中Na+/H+抗测剂的多样性和统一性。

项目成果

The murine genome contains one functional gene and two pseudogenes coding for the 16 kDa proteolipid subunit of vacuolar H+-ATPase

小鼠基因组包含 1 个功能基因和 2 个假基因，编码液泡 H -ATP 酶的 16 kDa 蛋白脂质亚基

• 发表时间: 2001
• 期刊: Gene 273
• 作者: Keiko Hayami;Takato Noumi;Hiroki Inoue;Ge-Hong Sun-Wada;Takao Yoshimizu;Hiroshi Kanazawa
• 通讯作者: Hiroshi Kanazawa

Norihiro Nakamura, Y, Miyake, M.Matsushita, S.Tnaka, H.Inoue, H.Kanazawa: "KIFIBb2, capable of interacting with CHP, is localized to Synaptic vesicles"J. Biochem.. 132. 483-491 (2002)

Norihiro Nakamura、Y、Miyake、M.Matsushita、S.Tnaka、H.Inoue、H.Kanazawa：“KIFIBb2 能够与 CHP 相互作用，定位于突触小泡”J.

KIF1Bb2, capable of interacting with CHP, is localized ti synaptic vesicles

KIF1Bb2 能够与 CHP 相互作用，位于突触小泡中

• 发表时间: 2002
• 期刊: J.Biochem. 132
• 作者: N.Nakamura;Y.
• 通讯作者: Y.

Hiroki Inoue, Yutaka Nakamura, Mana Nagita, Tomoyo Takai, Miho Masuda, Norihio Nakamura, Hiroshi Kanazawa: "Calcineurin homologous protein isoform 2 (CHP2),Na^+/H^+ exchangers-binding protein, is expressed in intestinal epithelium"Biol.Pharm.Bull.. 26. 14

Hiroki Inoue、Yutaka Nakamura、Mana Nagita、Tomoyo Takai、Miho Masuda、Norihio Nakamura、Hiroshi Kanazawa：“钙调磷酸酶同源蛋白亚型 2 (CHP2)，Na^ /H^ 交换器结合蛋白，在肠上皮中表达”Biol.Pharm

The murine genome contains one functional gene and two Pseudogene coding for the 16 kDa proteolipid subunit of vacuolar H+-ATPase

小鼠基因组包含 1 个功能基因和 2 个编码液泡 H -ATP 酶 16 kDa 蛋白脂质亚基的假基因

• 发表时间: 2001
• 期刊: Gene 273
• 作者: Suzuki N.;et al.;Keiko Hayami
• 通讯作者: Keiko Hayami