Synapse formation on neurons born in the adult hippocampus
Synapse formation on neurons born in the adult hippocampus
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DOI：
10.1038/nn1908
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发表时间：
2007-06-01
影响因子：
25
通讯作者：
Gage, Fred H.
中科院分区：
文献类型：
--
作者：
Toni, Nicolas;Teng, E. Matthew;Gage, Fred H.
虽然成年人的大脑中产生了新的功能性神经元，但人们对它们如何整合到成熟的网络中知之甚少。本研究利用共聚焦显微镜、电子显微镜和活体成像技术探讨了成年小鼠海马神经元突触发生的机制。我们报告，新的神经元，类似于成熟的颗粒神经元，轴体，轴树和轴棘突触接触。与它们在突触发生中的假定作用一致，树突状丝状伪足在成熟的早期阶段更丰富，并且当在三维中分析时，在已经与其他神经元突触的预先存在的终扣的200 nm内发现所有丝状伪足的尖端。此外，树突棘主要突触的多突触扣，这表明最初的接触优先与预先存在的扣已经参与了突触。新神经元的连通性持续变化，直到至少2个月，在第一个树突突起形成很久之后。
Although new and functional neurons are produced in the adult brain, little is known about how they integrate into mature networks. Here we explored the mechanisms of synaptogenesis on neurons born in the adult mouse hippocampus using confocal microscopy, electron microscopy and live imaging. We report that new neurons, similar to mature granule neurons, were contacted by axosomatic, axodendritic and axospinous synapses. Consistent with their putative role in synaptogenesis, dendritic filopodia were more abundant during the early stages of maturation and, when analyzed in three dimensions, the tips of all filopodia were found within 200 nm of preexisting boutons that already synapsed on other neurons. Furthermore, dendritic spines primarily synapsed on multiple-synapse boutons, suggesting that initial contacts were preferentially made with preexisting boutons already involved in a synapse. The connectivity of new neurons continued to change until at least 2 months, long after the formation of the first dendritic protrusions.