Functional analysis of the glutamate receptor δ2 subunit in the motor learning

谷氨酸受体δ2亚基在运动学习中的功能分析

• 批准号: 10680716
• 负责人: MORI Hisashi
• 金额: $ 2.18万
• 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 (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10680716/
• 关键词: Glutamate receptor; GluRδ2 subunit; Motor learning; Eye blink conditioning; Cerebellar Purkinje cells; Cerebellar granule cells; Cre recombinase; 遺伝子ノックアウト; テトラサイクリンオペロン; 小脳

Glutamate receptor (GluR) channels mediate most of fast excitatory synaptic transmission in the vertebrate central nervous system. The GluRδ2 subunit expressed specifically in cerebellar Purkinje cells, and it's ablation resulted in impairements of long term depression (LTD), motor coordination, and refinement of synapses. GluRδ2 deficient mice received classical eyeblink conditioning. In the delay paradigm in which the conditioned stimuluus (CS) overlapped temporally with unconditioned stimulus (US). GluRδ2 mutant mice exhibited a severe impairment in learning. However, in the trace paradigm in which a stimulus-free trace interval intervened between the CS and US. GluRδ2 mutant mice learned as successfully as wild-type mice. Therefore, cerebellar LTD is essential in the delay paradigm, but not in the trace paradigm, suggesting an alteration of cerebellar neural substrates underlying eyeblink conditioning depending on the temporal overlap of the CS and US. Furthermore, to develop a cell type-specific and temporal regulation system of gene targeting in the cerebellum, we employed the NMDA receptor GluRε3 subunit gene and Cre recombinase-progesterone receptor fusion (CrePR) gene in combination. We established a ECP25 transgenic mouse line that strongly expressed the CrePR mRNA selectively in the granule cells of the cerebellum. We showed that antiprogestins could induce the recombinase activity of CrePR fusion protein of ECP25 mouse in the cerebellar granule cells. Thus, the established mouse line will provide a valuable tool to investigate the mechanism of cerebellar function by manipulating molecules in the temporally regulated and granule cell-specific manner.

谷氨酸受体 (GluR) 通道介导脊椎动物特别是中枢神经系统中的大部分快速兴奋性突触传递。GluRδ2 亚基在小脑浦肯野细胞中表达，其消融会导致长期抑郁 (LTD)、运动协调和精细化的损害。 GluRδ2 缺陷小鼠接受经典的眨眼条件反射，其中条件刺激（CS）。与无条件刺激 (US) 暂时重叠的小鼠表现出严重的学习障碍，但在无刺激跟踪间隔的情况下，GluRδ2 突变小鼠的学习效果与野生型小鼠一样成功。因此，小脑LTD在延迟范式中至关重要，但在追踪范式中则不然，这表明眨眼条件作用下小脑神经基质的改变取决于CS和US的时间重叠。为了开发小脑中强效基因靶向的细胞类型特异性和时间调控系统，我们结合使用 NMDA 受体 GluRε3 亚基基因和 Cre 重组酶-黄体酮受体融合 (CrePR) 基因，建立了表达 ECP25 转基因小鼠系。 CrePR mRNA 选择性存在于小脑颗粒细胞中。我们发现抗孕激素可以诱导 CrePR 融合蛋白的重组酶活性。小脑颗粒细胞中的 ECP25 小鼠因此，建立的小鼠系将提供一个有价值的工具，通过以时间调节和颗粒细胞特异性的方式操纵分子来研究小脑功能的机制。

项目成果

Kiyama, Y., et al.: "Increased thresholds for long-term potentiation and contexual learning in mice lacking the NMDA-type glutamate receptor ε1 subunit"Journal of Neuroscience. 18. 6704-6712 (1998)

Kiyama, Y.等人：“缺乏 NMDA 型谷氨酸受体 ε1 亚基的小鼠的长期增强和情境学习阈值增加”《神经科学杂志》18. 6704-6712 (1998)。

Mori Hisashi et al.: "Role of the carboxy-terminal region of the GluR ε_2 Subumit in symaptic localization of the NMDA receptor channel" Neuron. 21. 571-580 (1998)

Mori Hisashi 等人：“GluR ε_2 亚基的羧基末端区域在 NMDA 受体通道的交感定位中的作用”Neuron。 21. 571-580 (1998)

Mika Tsujita et al.,: "Cerebellar Granule Cell-Specific and Inducible Expression of Cre Recombinase in the Mouse"Journal of Neuroscience. 19(23). 10318-10323 (1999)

Mika Tsujita 等人，“Cre 重组酶在小鼠中的小脑颗粒细胞特异性和诱导表达”神经科学杂志。

Morikawa E. et al.: "Attenuation of focal ischemic brain injury in mice deficient in the ε1 (NR2A) subunit of NMDA receptor."J. Neurosci.. 18. 9727-9732 (1998)

Morikawa E. 等人：“NMDA 受体 ε1 (NR2A) 亚基缺陷的小鼠局灶性缺血性脑损伤的减轻。J. Neurosci.. 18. 9727-9732 (1998)

Kiyama Yuji et al.: "Increased threshelds for long-term potentiation and contextual learning in mice lacking the NMDA-type glutamate receptor ε_1 subunit" Journal of Neuroscience. 18. 6704-6712 (1998)

Kiyama Yuji 等人：“缺乏 NMDA 型谷氨酸受体 ε_1 亚基的小鼠长期增强和情境学习的阈值增加”《神经科学杂志》18. 6704-6712 (1998)。