Molecular Basis of Circadian Cytosolic Calcium Rhythms

昼夜胞质钙节律的分子基础

• 批准号: 16300104
• 负责人: IKEDA Masayuki
• 金额: $ 9.8万
• 依托单位: University of Toyama (2005-2007)Osaka Bioscience Institute (2004)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16300104/
• 关键词: Brain Slice Cultures; Clock Genes; Suprachiasmatic Nucleus; FRET; Cytosolic Calcium; サーカディアンリズム; 体内時計; 蛍光タンパク; ミトコンドリア; 睡眠・覚醒

The hypothalamic suprachiasmatic nucleus (SCN) has a pivotal role for the mammalian circadian clock system. We have demonstrated circadian rhythms in cytosolic Ca^(2+) concentrations in cultured SCN neurons and proposed that intracellular Ca^(2+) is a candidate messenger which mediates cellular input/output signals to/from the molecular loop. However, essential regulatory genes to drive circadian Ca^(2+) rhythms were currently unknown. The present research aims to elucidate the molecular mechanism underlying the generation of circadian Ca^(2+) rhythms in clock cells. First, we examined effects of mPer1/mPer2 antisense mRNAs on SCN neurons whereas failed to observe their effects on circadian rhythms in cytosolic Ca^(2+) and action potential firings. Second, we used several gene knockout mice lacking clock genes. The SCN neurons from the Cry1/Cry2 double knockout mice represented arrhythmic Ca^(2+) oscillations and those from the RORα knockout mice represented reduced amplitude Ca^(2+) o … More scillations. Thus, we further over-expressed native mouse Bmal1 or dominant negative Bmal1 into the SCN. These treatments resulted in a significant reduction in circadian Ca^(2+) oscillations in SCN neurons. Therefore, we concluded that endogenous expression of BMAL1 is essential for the generation of circadian Ca^(2+) rhythms and thus for the physiological activity rhythms in SCN neurons.The present study also analyzed process of photic inputs to SCN neurons regarding the mobilization of cytosolic Ca^(2+) and expression of clock genes. We found light-pulse-induced mPer1/2 gene expression in the SCN and behavioral-phase-shifts were significantly reduced in cholecystokinin (CCK)-A receptor knockout mice. We demonstrated that CCK-A receptors were located predominately on glycinergic amacrine cells, but not retino-recipient SCN neurons. Moreover, Ca^(2+) imaging analysis demonstrated that the CCK-A agonist, CCK-8s, mobilized intracellular Ca^(2+) in amacrine cells but not retino-recipent SCN neurons. These data indicate a novel function of CCK-A receptors as part of the cellular mechanism underlying circadian photo-entrainment via amacrine-cell-mediated signal transduction pathways. Less

下丘脑视交叉上核（SCN）在哺乳动物生物钟系统中起着关键作用。我们已经证明了培养的SCN神经元胞浆Ca^（2+）浓度的昼夜节律，并提出胞内Ca^（2+）是一种候选信使，它介导细胞输入/输出信号到分子环或从分子环输出信号。然而，目前还不知道驱动Ca^（2+）昼夜节律的重要调控基因。本研究旨在阐明生物钟细胞中Ca^（2+）昼夜节律产生的分子机制。首先，我们研究了mPer 1/mPer 2反义mRNA对SCN神经元的影响，但未能观察到它们对胞浆Ca^（2+）和动作电位放电的昼夜节律的影响。其次，我们使用了几个缺乏时钟基因的基因敲除小鼠。来自Cry 1/Cry 2双基因敲除小鼠的SCN神经元表现为钙离子振荡，而来自RORα基因敲除小鼠的SCN神经元表现为钙离子振荡幅度降低。 ...更多信息 振动因此，我们进一步将天然小鼠Bmal 1或显性阴性Bmal 1过表达到SCN中。这些处理导致SCN神经元的昼夜Ca^（2+）振荡显著减少。因此，我们认为BMAL 1的内源性表达对于SCN神经元内Ca^（2+）昼夜节律的产生以及生理活动节律的形成是必不可少的，本研究还分析了SCN神经元内光输入过程中胞浆Ca^（2+）的动员和时钟基因的表达。我们发现，光脉冲诱导的mPer 1/2基因表达的SCN和行为相移显着减少胆囊收缩素（CCK）-A受体基因敲除小鼠。我们证明，CCK-A受体主要位于甘氨酸能无长突细胞，但不是视网膜受体SCN神经元。此外，Ca^（2+）成像分析表明，CCK-A激动剂CCK-8 s可调动无长突细胞内的Ca^（2+），但对视网膜沉淀的SCN神经元无影响。这些数据表明，一种新的功能的CCK-A受体的细胞机制的一部分，昼夜光夹带通过无长突细胞介导的信号转导途径。少

项目成果

Brain oxidation is an initial process in sleep induction

• DOI: 10.1016/j.neuroscience.2004.09.057
• 发表时间: 2005-01-01
• 期刊: NEUROSCIENCE
• 影响因子: 3.3
• 作者: Ikeda, M;Ikeda-Sagara, M;Inoué, S
• 通讯作者: Inoué, S

Retinal signal processing for the circadian clock inputs via amacrine cell cholecystokinin-A receptors

通过无长突细胞胆囊收缩素-A 受体对生物钟输入进行视网膜信号处理

• 发表时间: 2007
• 作者: Ikeda;M.;Morita;M.;Takiguchi;S.;Funakoshi;A.;Shimazoe;T.
• 通讯作者: T.

(2008)Cholecystokinin-A receptors regulate photic input pathways to the circadian clock

(2008)胆囊收缩素-A 受体调节生物钟的光输入途径

• 发表时间: 2008
• 期刊: The FASEB Journal 22
• 作者: Shimazoe;T;Morita;M;Ogiwara;S;Kojiya;T;Goto;J;Kamakura;M;Moriya;T;Shinohara;K;Takiguchi;S;Kono;A;Miyasaka;K;Funakoshi;A;Ikeda;M^
• 通讯作者: M^<CA>

Role of nociceptin and opioid receptor like 1 (ORL1) on entrainment function in the rat suprachiasmatic nucleus.

伤害感受肽和阿片受体样 1 (ORL1) 对大鼠视交叉上核夹带功能的作用。

• 发表时间: 2006
• 期刊: Neuroscience 137
• 作者: Sugino T;Shimazoe T;Kanemoto Y;Ikeda M;Watanabe S
• 通讯作者: Watanabe S

Linkage between cellular oscillations and behavioral circadian rhythms from Drosophila to mammals

从果蝇到哺乳动物的细胞振荡和行为昼夜节律之间的联系

• 发表时间: 2007
• 期刊: J. Physiol. Sci. 57
• 作者: D.Kawawaki;T.Shibata;N.Goda;K.Doya;M.Kawato;Ikeda M
• 通讯作者: Ikeda M