Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA.
Science. 2014 Apr 11;344(6180):194-7. doi: 10.1126/science.1248805.
The mammalian olfactory system has the natural capacity to regenerate throughout the animal's life span. Despite constant neurogenesis, olfactory sensory neurons project to precise, stereotypical positions in the brain. Here, we identify a critical period of olfactory sensory axon targeting during postnatal development in mouse. Perturbing axon projection beyond postnatal day 7 permanently disrupts targeting specificity of the sensory neurons. In addition, we find that the establishment of the convergence map requires perinatal sensory neurons. Late-born neurons appear to connect with prospective glomeruli based on homotypic interactions among neurons expressing the same odorant receptor. Our results reveal a developmental switch in axon guidance and a mechanism of circuit integration of adult-born neurons.
哺乳动物的嗅觉系统在其整个生命周期内都具有自然的再生能力。尽管持续不断地有神经元生成，但嗅觉感觉神经元仍投射到大脑中精确的、刻板的位置。在这里，我们确定了在小鼠出生后的发育过程中，嗅觉感觉轴突靶向的一个关键时期。在出生后 7 天以后干扰轴突投射会永久破坏感觉神经元的靶向特异性。此外，我们发现，汇聚图的建立需要围产期的感觉神经元。迟发性神经元似乎基于表达相同气味受体的神经元之间的同型相互作用与预期的肾小球建立连接。我们的研究结果揭示了轴突导向的发育开关和成年新生神经元的电路整合机制。
