Integration of multi-oscillator circadian clock: in vivo and ex vivo imaging of clock gene expression

我们的目的是阐明中央生物钟震荡细胞的相互耦合机制，视交叉上核（SCN）。我们开发了一种体内监测系统，用于监测未麻醉和不受约束动物SCN的时钟基因表达，并开发了一种长期和实时的体外监测系统，用于监测培养SCN切片的整个神经元细胞内Ca++水平。我们证明了所有SCN神经元在Ca++水平上表现出强大的昼夜节律，这是拓扑特异性的，并且SCN背侧和腹侧起搏器之间的耦合依赖于突触相互作用。我们进一步证明，时钟基因Cry对断奶期前后SCN中振荡细胞网络的发展至关重要。

We aimed to clarify mutual coupling mechanisms of oscillator cells in the central circadian clock, the suprachiasmatic nucleus (SCN). We developed in vivo monitoring systems for clock gene expression from the SCN of unanesthetized and unrestrained animals and a long-term and real-time ex vivo monitoring systems for intracellular Ca++ levels from the entire neurons of cultured SCN slices. We demonstrated that all SCN neurons exhibit robust circadian rhythms in Ca++ levels which are topologically specific and the coupling between the pacemakers in the dorsal and ventral SCN depends on synaptic interaction. We further demonstrated that clock gene Cry is essential for the development of oscillator cell network in the SCN for the coherent rhythm expression which takes place around weaning period.