Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA.
Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA; Department of Anatomy and Cell Biology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA.
Neuron. 2018 Dec 5;100(5):1066-1082.e6. doi: 10.1016/j.neuron.2018.09.051. Epub 2018 Oct 25.
In the developing brain, heightened plasticity during the critical period enables the proper formation of neural circuits. Here, we identify the "navigator" neurons, a group of perinatally born olfactory sensory neurons, as playing an essential role in establishing the olfactory map during the critical period. The navigator axons project circuitously in the olfactory bulb and traverse multiple glomeruli before terminating in perspective glomeruli. These neurons undergo a phase of exuberant axon growth and exhibit a shortened lifespan. Single-cell transcriptome analyses reveal distinct molecular signatures for the navigators. Extending their lifespan prolongs the period of exuberant growth and perturbs axon convergence. Conversely, a genetic ablation experiment indicates that, despite postnatal neurogenesis, only the navigators are endowed with the ability to establish a convergent map. The presence and the proper removal of the navigator neurons are both required to establish tight axon convergence into the glomeruli.
在发育中的大脑中，关键期的高度可塑性使神经回路得以正常形成。在这里，我们发现“导航者”神经元，一群在围产期出生的嗅觉感觉神经元，在关键期内发挥了在嗅球中建立嗅觉图的重要作用。导航者轴突迂回投射到嗅球中，并在终止于特定的嗅球之前穿过多个嗅小球。这些神经元经历了一个旺盛的轴突生长阶段，并表现出寿命缩短的现象。单细胞转录组分析揭示了导航者的独特分子特征。延长其寿命会延长旺盛生长的时期，并扰乱轴突的收敛。相反，遗传消融实验表明，尽管有出生后的神经发生，但只有导航者才具有建立收敛图的能力。导航者神经元的存在和适当去除都是建立轴突紧密收敛到嗅小球所必需的。
