Rapid and continuous activity-dependent plasticity of olfactory sensory input.
Rapid and continuous activity-dependent plasticity of olfactory sensory input.
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DOI：
10.1038/ncomms10729
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发表时间：
2016-02-22
影响因子：
16.6
通讯作者：
Belluscio L
中科院分区：
文献类型：
--
作者：
Cheetham CEJ;Park U;Belluscio L
新神经元的加入使成人大脑回路的可塑性和修复成为可能。成体神经发生是哺乳动物嗅觉系统的一个重要特征，在整个生命过程中，新的嗅觉神经元(OSN)连接到高度组织的嗅球(OB)回路。然而，新的出生后产生的OSN何时第一次形成突触，以及OSN是否在成熟后保留突触发生的能力，都是未知的。因此，成人出生的OSN的整合如何有助于终生OB可塑性尚不清楚。在这里，我们使用电子显微镜、光遗传学激活和活体时间推移成像相结合的方法来显示新生成的OSN形成高度动态的突触，并能够在小鼠OB中引发强大的刺激锁定神经元放电。此外，我们证明，成熟的OSN轴突经历持续的活性依赖的突触重塑，这种重塑持续到成年。因此，OSN的突触发生为OB的可塑性和修复提供了持续的潜力，这比单纯的OSN替代要快得多。新的嗅觉神经元(OSN)在整个生命过程中都会连接到嗅球回路。在这里，作者表明，新生成的OSN形成高度动态的突触，并可以在OB神经元中引发功能反应，而成熟的OSN保持高水平的活性依赖的突触重组。
Incorporation of new neurons enables plasticity and repair of circuits in the adult brain. Adult neurogenesis is a key feature of the mammalian olfactory system, with new olfactory sensory neurons (OSNs) wiring into highly organized olfactory bulb (OB) circuits throughout life. However, neither when new postnatally generated OSNs first form synapses nor whether OSNs retain the capacity for synaptogenesis once mature, is known. Therefore, how integration of adult-born OSNs may contribute to lifelong OB plasticity is unclear. Here, we use a combination of electron microscopy, optogenetic activation and in vivo time-lapse imaging to show that newly generated OSNs form highly dynamic synapses and are capable of eliciting robust stimulus-locked firing of neurons in the mouse OB. Furthermore, we demonstrate that mature OSN axons undergo continuous activity-dependent synaptic remodelling that persists into adulthood. OSN synaptogenesis, therefore, provides a sustained potential for OB plasticity and repair that is much faster than OSN replacement alone. New olfactory sensory neurons (OSNs) wire into olfactory bulb circuits throughout life. Here, the authors show that newly generated OSNs form highly dynamics synapses and can elicit functional responses in OB neurons, while mature OSNs retain a high level of activity-dependent synaptic reorganisation.