Dual origins of the intracellular circadian calcium rhythm in the suprachiasmatic nucleus.
Dual origins of the intracellular circadian calcium rhythm in the suprachiasmatic nucleus.
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DOI：
10.1038/srep41733
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发表时间：
2017-02-03
影响因子：
4.6
通讯作者：
Honma KI
中科院分区：
文献类型：
--
作者：
Enoki R;Ono D;Kuroda S;Honma S;Honma KI
在哺乳动物中，主生物钟位于视交叉上核（SCN），其中大多数神经元显示细胞内Ca 2+水平的昼夜节律。然而，这些Ca 2+节律的起源在很大程度上仍然未知。在这项研究中，我们成功地监测了细胞内的昼夜Ca 2+节律与昼夜PER 2和放电节律在一个单一的SCN切片离体，这使我们能够探索的起源。在Cry 1/Cry 2双基因敲除小鼠中，PER 2昼夜节律和Ca 2+节律之间的相位关系显著改变，但PER 2昼夜节律和放电节律之间的相位关系不显著改变，这显示SCN中细胞间同步化的丧失。此外，在Cry 1/Cry 2双基因敲除小鼠，昼夜Ca 2+节律被废除的背外侧SCN，但维持在大多数的腹内侧SCN。这些发现表明，细胞内的昼夜Ca 2+节律是由外源性和内源性成分参与PER 2的表达。
In mammals, the master circadian clock is located in the suprachiasmatic nucleus (SCN), where most neurons show circadian rhythms of intracellular Ca2+ levels. However, the origin of these Ca2+ rhythms remains largely unknown. In this study, we successfully monitored the intracellular circadian Ca2+ rhythms together with the circadian PER2 and firing rhythms in a single SCN slice ex vivo, which enabled us to explore the origins. The phase relation between the circadian PER2 and Ca2+ rhythms, but not between the circadian PER2 and firing rhythms, was significantly altered in Cry1/Cry2 double knockout mice, which display a loss of intercellular synchronization in the SCN. In addition, in Cry1/Cry2 double knockout mice, circadian Ca2+ rhythms were abolished in the dorsolateral SCN, but were maintained in the majority of the ventromedial SCN. These findings indicate that intracellular circadian Ca2+ rhythms are composed of an exogenous and endogenous component involving PER2 expression.