Abstract:
The nucleus incertus (NI), a conserved hindbrain structure implicated in the stress response, arousal, and memory, is a major site for production of the neuropeptide relaxin-3. On the basis of goosecoid homeobox 2 (gsc2) expression, we identified a neuronal cluster that lies adjacent to relaxin 3a (rln3a) neurons in the zebrafish analogue of the NI. To delineate the characteristics of the gsc2 and rln3a NI neurons, we used CRISPR/Cas9 targeted integration to drive gene expression specifically in each neuronal group, and found that they differ in their efferent and afferent connectivity, spontaneous activity, and functional properties. gsc2 and rln3a NI neurons have widely divergent projection patterns and innervate distinct subregions of the midbrain interpeduncular nucleus (IPN). Whereas gsc2 neurons are activated more robustly by electric shock, rln3a neurons exhibit spontaneous fluctuations in calcium signaling and regulate locomotor activity. Our findings define heterogeneous neurons in the NI and provide new tools to probe its diverse functions.
摘要:
细胞核(NI),与应激反应有关的保守的后脑结构,唤醒,和记忆,是产生神经肽松弛素-3的主要位点。基于Goosecoid同源盒2(gsc2)表达式,我们在NI的斑马鱼类似物中确定了与松弛素3a(rln3a)神经元相邻的神经元簇。为了描绘gsc2和rln3aNI神经元的特征,我们使用CRISPR/Cas9靶向整合来驱动每个神经元组中的基因表达,发现它们的传出和传入连通性不同,自发活动,和功能属性。gsc2和rln3aNI神经元具有广泛发散的投射模式,并支配中脑足间核(IPN)的不同亚区。而gsc2神经元被电击更强烈地激活,rln3a神经元表现出自发的钙信号波动并调节运动活动。我们的发现定义了NI中的异质神经元,并提供了新的工具来探测其不同的功能。