ANALYSIS OF PHYSIOLOGICAL FUNCTION OF LIPID SIGNALLING SYSTEM

脂质信号系统的生理功能分析

基本信息

批准号：
18370053
负责人：
KANAHO Yasunori
金额：
$ 10.99万
依托单位：
University of Tsukuba
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18370053/
关键词：
single transduction lipid kinase synaptic vesicle ARF6 knockout mice endocytosis AP-2 complex PIP5K 低分子量G蛋白質アレルギー神経 PIP5Kγ661 シナプス小胞

项目摘要

The lipid kinase phosphatidylinositol 4-phosphate 5-kinase (PIP5K) phosphorylates phosphatidylinositol 4-phosphate to produce phosphatidylinositol 4,5-bisphosphate (PIP2), which functions as a lipid signaling molecule. Three isozymes for mammalian PIP5K, α β and γ, and three splicing variants of γ type of PIP5K, γ635, γ661 and γ687, have been identified. We have been investigating activation mechanisms and physiological functions of each PIP5K isozyme to understand the molecular multiplicity of PIP5K. During 2 years of this project, we obtained the results described below.1. Specific partner protein of PIP5K γ661PIP5K γ661 of PIP5K isozymes and splicing variants, was found to specifically interact with and is activated by the adaptor complex AP-2 in mouse hippocampal neurons. Furthermore, it was found that the interaction of these molecules is absolutely required for the clathrin-dependent synaptic vesicle endocytosis induced by depolarization, in mouse hippocampal neurons.2. Specific partner protein of PIP5KβPIP5Kβ of PIP5K isozymes specifically interact with KIF2A. The interaction stimulated PIP5Kβ kinase activity and microtubule depolymerizing activity of KIF2A. Finally, the interaction of these two molecules was found to negatively regulate axonal outgrowth of mouse hippocampal neurons.3. PIP5K binding site for its activator ARF6The small G protein ARF6 activates PIP5K. We identified that ARF6 binds to the kinase core domain of PIP5K, which is highly conserved among PIP5K isozymes.4. Preparation and analysis of PIP5K α knockout miceWe prepared PIP5K α knockout mice, which have not yet been reported. These mice were apparently healthy and any defects were not observe.

脂质激酶磷脂酰肌醇 4-磷酸 5-激酶 (PIP5K) 磷酸化磷脂酰肌醇 4-磷酸，产生磷脂酰肌醇 4,5-二磷酸 (PIP2)，其充当哺乳动物 PIP5K、α β 和 γ 的三种同工酶。 PIP5K γ 型的三种剪接变体， γ635、γ661 和γ687 已被鉴定。我们一直在研究每种PIP5K 同工酶的激活机制和生理功能，以了解PIP5K 的分子多样性。在该项目的2 年中，我们获得了如下结果。 1． PIP5K γ661PIP5K γ661 的 PIP5K 同工酶和剪接变体，被发现与 PIP5K γ661 特异性相互作用并被激活此外，还发现这些分子的相互作用是小鼠海马神经元去极化诱导的网格蛋白依赖性突触小泡内吞作用所必需的。2． PIP5K 同工酶与 KIF2A 特异性相互作用，这种相互作用刺激了 PIP5Kβ 激酶活性和微管解聚活性。最后，发现这两个分子的相互作用对小鼠海马神经元的轴突生长有负向调节作用。3. PIP5K 其激活剂 ARF6 的结合位点小 G 蛋白 ARF6 激活 PIP5K。 PIP5K在PIP5K同工酶中高度保守。4．PIP5Kα基因敲除小鼠的制备与分析我们制备了PIP5K。 α基因敲除小鼠，尚未有报道。这些小鼠显然是健康的，并且没有观察到任何敲除缺陷。