Roles of Tyrosine Phosphorylation in The Development and Plasticity of The Central Nervous System

酪氨酸磷酸化在中枢神经系统发育和可塑性中的作用

基本信息

批准号：
11308031
负责人：
YAMAMOTO Tadashi
金额：
$ 24.9万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11308031/
关键词：
Novel tyrosine kinases Central nervous system RT-PCR in silico screening Signal transduction ALK Lyn Filter kinase assay チロシンキナーゼチロシンフォスファターゼシナプス伝達神経回路網 NMDA受容体 Srcファミリー SSH法 ERBB2 LYN フィルターキナーゼアッセイ

项目摘要

We performed three types of studies that are (1) the search of the novel tyrosine kinases expressed in the central nervous system, (2) identification of proteins that are respectively involved in Lyn and ALK tyrosine kinases-mediated signaling pathways in the central nervous system, (3) characterization of a protein-tyrosine phosphatase PTPMEG that associates with ionotropic glutamate receptors. The followings are the summary of the study.(1) By performing differential screening of RT-PCR products and in silico screening, we identified novel kinases that included the one termed BREK (brain enriched kinase). We also identified a homologue of BREK termed BREK2. BREK and BREK2 are similar to AATYK that has been reported to be a tyrosine kinase involved in regulation of apoptotic death of neurons. Unlike AATYK, both BREK and BREK2 are dual specificity kinases showing strong serine/threonine and weak tyrosine kinase activities. Expression of BREK is high in the central nervous system, such as in cerebral cortex and olfactory bulb. BREK becomes phosphorylated upon NGF stimulation of cultured neuronal cells, suggesting that BREK is involved in neurite extension.(2) By employing filter kinase assay and yeast two-hybrid screening, we identified BANK and SNT2 as substrates of Lyn and ALK, respectively. BANK is an adaptor protein that links Lyn to IP_3 receptor (IP_3R). We showed that formation of Lyn/BANK/IP_3R resulted in tyrosine phosphorylation of IP_3R, which is known to upregulate the channel activity of IP_3R. Regarding SNT2, we showed that SNT2 was critically important for ALK-mediated signaling.(3) We also identified various signaling molecules that were associated with ionotropic glutamate receptors. One of them is PTPMEG that associates with GluRd2 and NMDA receptor subunits NR2A. PTPMEG is expressed high in the thalamus and affects the level of tyrosine phosphorylation of NR2A, suggesting that PTPMEG is involved in controlling synaptic plasticity.

我们进行了三种类型的研究，这些研究是（1）搜索中枢神经系统中表达的新型酪氨酸激酶，（2）鉴定中枢神经系统中与LYN和ALK酪氨酸激酶介导的信号传导途径分别涉及的蛋白质，（3）与离子型谷氨酸受体相关的蛋白 - 酪氨酸磷酸酶PTPMEG的表征。以下是研究的摘要。（1）通过对RT-PCR产物进行差异筛选，在计算机筛选中，我们确定了包括称为Brek（脑富集激酶）的新型激酶。我们还确定了Brek称为Brek2的同源物。 Brek和Brek2类似于AATYK，据报道是参与神经元凋亡死亡调节的酪氨酸激酶。与Aatyk不同，Brek和Brek2都是双重特异性激酶，显示出强烈的丝氨酸/苏氨酸和弱酪氨酸激酶活性。中枢神经系统中的BREK表达很高，例如脑皮质和嗅球。在NGF刺激培养的神经元细胞的情况下，BREK变得磷酸化，这表明BREK参与了神经突的延伸。（2）通过使用过滤器激酶测定和酵母两杂化筛选，我们分别将Bank和SNT2鉴定为Lyn和Alk的底物。银行是将LYN与IP_3受体（IP_3R）联系起来的衔接蛋白。我们表明，LYN/BANK/IP_3R的形成导致IP_3R的酪氨酸磷酸化，已知可以上调IP_3R的通道活动。关于SNT2，我们表明SNT2对于ALK介导的信号传导至关重要。（3）我们还鉴定了与离子型谷氨酸受体相关的各种信号分子。其中之一是PTPMEG，它与Glurd2和NMDA受体亚基NR2A相关。 ptpmeg在丘脑中表达很高，并影响NR2A的酪氨酸磷酸化水平，这表明PTPMEG参与控制突触可塑性。