Molecular and Cell Biological Analysis of Lipid Kinases in Relation to Signaling and Vesicle Traffic.

与信号传导和囊泡运输相关的脂质激酶的分子和细胞生物学分析。

基本信息

批准号：
09470001
负责人：
KONDO Hisatake
金额：
$ 8.32万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

The cloning and characterization of a novel class II phosphoinositide (PI) 3-kinase was succeeded from the cDNA library of regenerating rat liver. This enzyme molecule composed of 1505 amino acids contained a C2 domain and displayed a restricted substrate specificity for PtdIns and PtdIns 4-P and, thus termed PI3K-IIgamma. This molecule was localized in the juxtanuclear Golgi region in the over-expressed in vitro cells. The mRNA expression was confined to the liver throughout the development and its expression increased during liver regeneration after partial hepatectomy.The gene expression for a subtype of phosphatidate (PA) phosphatase termed Dri42 was confined to the ventricular germinal zone of embryonic brain. PAP catalyses a dephosphorylation of PA to produce diacylglycerol (DG), an reverse process of phosphorylation by DG kinase whose molecular identification has been intensively performed by us. The localization of mRNAs for synaptojanin, inositol 5-phosphatase, in the brain was also revelaed by in situ hybridization histochemistry. Synaptojanin 1 mRNA was expressed in almost all neurons of the brain throughout developing and mature stages while synaptojanin 2 mRNA was first detected in neurons on early postnatal stages and the expression was evident in the white matters presumptive oligodendrocytes as the postnatal development proceeded. All these findings on dephosphorylation were instructive for understanding the significance of phosphorylation by lipid kinases.The gene expression localization of CDP-DG synthase and phosphatidylinositol synthase, both of which are involved in the two sequential PI-metabolic processes, was analyzed and some discrepant expression patterns were found spatio-temporally in developing and mature brain. The gene expression localization of phospholipase D in the brain is also under way by in situ hybridization histochemistry.

新型II类磷酸肌醇（PI）3-激酶的克隆和表征从再生大鼠肝脏的cDNA文库中取得了成功。该酶分子由1505个氨基酸组成，其中包含一个C2结构域，并显示了PTDINS和PTDINS 4-P的受限底物特异性，因此称为PI3K-IIGAMMA。该分子位于过表达的体外细胞中的近核高尔基区。在整个发育过程中，mRNA表达局限于肝脏，其在部分肝切除术后肝脏再生过程中的表达增加。所谓的DRI42的磷酸磷酸酶（PA）磷酸酶亚型的基因表达局限于胚胎脑的心室生发区。 PAP催化PA的去磷酸化产生二酰基甘油（DG），DG激酶的磷酸化反向过程，其分子鉴定已由我们进行了强烈的进行。在原位杂交组织化学的原位杂交组织中，在大脑中，在大脑中，mRNA在大脑中的肌醇5-磷酸酶的定位。在整个发育阶段和成熟阶段，在几乎所有大脑的神经元中表达了Synaptojanin 1 mRNA，而在产后早期早期的神经元中首次在神经元中检测到突触素蛋白2 mRNA，并且随着产后的发展，白质少生细胞的表达很明显。所有这些关于去磷酸化的发现均具有指导性，可以理解脂质激酶的磷酸化的重要性。基因表达CDP-DG合酶和磷脂酰辛基醇合酶的定位，这两种均涉及两个顺序的PI-PI-代谢过程，并分析了一些差异的表达模式。磷脂酶D在大脑中的基因表达定位也通过原位杂交组织化学进行了。