cDNAs and antibodies for small GTP-binding proteins

小 GTP 结合蛋白的 cDNA 和抗体

基本信息

批准号：
03558019
负责人：
TAKAI Yoshimi
金额：
$ 10.24万
依托单位：
Kobe University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1993
项目状态：
已结题

项目摘要

There is the small GTP-binding protein (G protein) superfamily which consists of over fifty members. All members have monomeric proteins with Mrs between 20, 000 and 30, 000 which exhibit both GDP/GTP-binding and GTPase activities. In the present research project, we studied the functions and modes of activation of small G proteins and tried to prepare concerning cDNAs and antibodies as tools for certain diseases. Ras is the representative of this superfamily and is well known to regulate cell proliferation, differentiation, and transformation, but its modes of activation and action remain to be clarified. We characterized three GDP/GTP exchange proteins for Ras including Smg GDS, CDC25Mm, and mSos. We indentified a target protein for Ras and named it REKS, which phosphorylated MAP kinase kinase and thereby activated it in a Ras-dependent manner. Accumulating evidence suggests that Rho regulates certain functions through an actomyosin system. By use of C3 exoenzyme and Rho GDI, we showed that Rho regulated cell morphology, cell motility, membrane ruffling, cytokinesis, and smooth muscle contraction through an actomyosin system. Rab family is known to regulate intracellular vesicle transport, such as exocytosis, endocytosis, and transcytosis. Rab3A is a member of Rab family which is particularly implicated in neurotransmitter release from the synapse. We isolated the cDNA encoding a target protein for Rab3A, which selectively interacted with the GTP-bound form of Rab3A, and named it rabphilin-3A.These results suggest that small G proteins play crucial roles in various cell functions and that their cDNA and antibodies can be used at tools for diagnosis and treatment of certain diseases.

有一个小的GTP结合蛋白（G蛋白）超家族，由五十多个成员组成。所有成员的单体蛋白质具有20、000至30、000之间的MR，具有GDP/GTP结合和GTPase活性。在本研究项目中，我们研究了小G蛋白的激活功能和模式，并试图准备有关cDNA和抗体作为某些疾病的工具的准备。 RAS是该超家族的代表，众所周知可以调节细胞增殖，分化和转化，但其激活和作用方式仍有待阐明。我们表征了三种用于RA的GDP/GTP交换蛋白，包括SMG GD，CDC25MM和MSO。我们缩小了RAS的靶蛋白，并将其命名为REK，该蛋白磷酸化的MAP激酶激酶并以Ras依赖性方式激活了它。积累的证据表明，Rho通过肌动球蛋白系统调节某些功能。通过使用C3外酶和Rho GDI，我们表明Rho调节细胞形态，细胞运动，膜褶皱，细胞因子和平滑肌肉收缩，并通过肌动蛋白系统系统进行平滑肌肉收缩。已知RAB家族会调节细胞内囊泡的转运，例如胞吞作用，内吞作用和跨胞菌病。 Rab3a是Rab家族的成员，它特别涉及突触中的神经递质释放。我们分离了编码RAB3A的靶蛋白的cDNA，该cDNA与Rab3a的GTP结合形式有选择地相互作用，并将其命名为Rabphilin-3A。这些结果表明，小G蛋白在各种细胞功能中起着至关重要的作用，并且它们的cDNA和抗体可以用于诊断和治疗某些疾病的工具。