Molecular Mechanisms of Exocytotic Prpces and Its Spatio-temporal Regulation

胞吐过程的分子机制及其时空调控

基本信息

批准号：
15200030
负责人：
KUMAKURA Konosuke
金额：
$ 27.79万
依托单位：
Sophia University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2006
项目状态：
已结题

项目摘要

The aim of this research project is to elucidate the molecular mechanism of exocytotic process and its spatio-temporal regulation, and we have obtained the following results.1) Roles of PKC in vesicle recruitment.The facilitation of the vesicle recruitment from the reserve pool to the releasable pool by protein kinase C (PKC) is mediated predominantly by PKCα. PKCβ also increases the secretory function, but by a distinct mechanism. Vesicle recruitment was increased by PKC through the vesicle movement at the rate of 0.03-0.06 μm/s, and the facilitation was detected as an increase in the frequency of exocytotic events in the sustained response. The facilitation of the vesicle recruitment by PKC is accompanied with a substantial increase in the vesicle numbers beneathe the plasma membrane. The receptor molecule for the activated PKC, RACK1, seemed to have roles as anchoring and signaling molecules in the regulation.2) Roles of motor proteins in vesicle recruitment.The important role of actin-myosin interaction in the recruitment of chromaffin granules to the release sites has been suggested. In the present research, it was suggested that myosin-V is specifically involved in the vesicle recruitment, while myosin-I is involved in the general movement of the vesicles. In addition, myosin-ATPase was shown to be essential for the regulation of the vesicle recruitment in chromaffin cells. The inhibition of myosin-ATPase resulted a decrease in the vesicle numbers beneathe the plasma membrane.3) Regulation of SNARE complex.Binding of calmodulin to C-teminus of VAMP-2, and binding between SyntaxinlA and CaMkinase II regulate SNARE complex and are essential for exocytosis.

该研究项目的目的是阐明胞吐过程的分子机制及其时空调节，我们获得了以下结果。1）PKC在囊泡募集中的作用。囊泡募集的设施从储备库募集到蛋白质激酶C（PKC）释放的池（PKC）均由Protein Kinase C（PKC）介导了介导的杂物pkcin。 PKCβ还通过一种独特的机制增加了秘密功能。 PKC通过囊泡运动以0.03-0.06μm/s的速度增加了囊泡的募集，并且在持续反应中检测到该设施是胞外事件频率的增加。 PKC募集囊泡的设施伴随着质膜下方的囊泡数量大幅增加。活化的PKC RACK1的接收器分子似乎在调节中具有锚定和信号分子的作用。2）运动蛋白在囊泡募集中的作用。肌动蛋白 - 甲状腺素相互作用在释放到释放位点的募集中的重要作用。在本研究中，有人建议肌球蛋白V专门参与囊泡募集，而肌球蛋白I参与囊泡募集的一般运动。此外，肌球蛋白 - ATPase被证明对于调节铬脂细胞中的囊泡募集至关重要。肌球蛋白ATPase的抑制作用导致质膜下方的囊泡数量减少。3）调节SNARE复合物。将钙调蛋白结合到VAMP-2的C-Teminus上，并在Syntaxinla和Camkinase II之间结合c-teminus II调节SNARE复合物，并且对杂胞菌病至关重要。