Lateral diffusion drives constitutive exchange of AMPA receptors at dendritic spines and is regulated by spine morphology
Lateral diffusion drives constitutive exchange of AMPA receptors at dendritic spines and is regulated by spine morphology
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DOI：
10.1523/jneurosci.1235-06.2006
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发表时间：
2006-06-28
影响因子：
5.3
通讯作者：
Henley, Jeremy M.
中科院分区：
文献类型：
--
作者：
Ashby, Michael C.;Maier, Susie R.;Henley, Jeremy M.
突触特异性是突触可塑性的基本特征，但如果突触后膜蛋白可以在突触之间横向扩散，突触特异性信号是如何实现的尚不清楚。我们监测了成熟神经元表面AMPA受体（AMPAR）的运动，以研究横向扩散在构成型AMPAR运输中的作用，并评估膜结构对突触蛋白表面分布的影响。我们的数据表明，侧侧扩散是脊柱表面大量ampar持续交换的原因。此外，我们发现膜蛋白的一个普遍特征是它们进出刺的速度比非刺膜慢。这表明侧向扩散依赖于脊柱形态，并在脊柱颈部受到限制。这些结果证明了横向扩散在AMPAR蛋白种群运输中的重要性，并为脊柱结构如何通过区隔横向扩散来维持突触特异性，从而增加膜蛋白在单个突触附近的停留时间提供了新的见解。
Synapse specificity is a basic feature of synaptic plasticity, but it remains unclear how synapse-specific signaling is achieved if postsynaptic membrane proteins can diffuse laterally between synapses. We monitored movements of AMPA receptors (AMPARs) on the surface of mature neurons to investigate the role of lateral diffusion in constitutive AMPAR trafficking and to assess the influence of membrane architecture on the surface distribution of synaptic proteins. Our data show that lateral diffusion is responsible for the continual exchange of a substantial pool of AMPARs at the spine surface. Furthermore, we found that a general characteristic of membrane proteins is that their movement into and out of spines is slow compared with that in nonspiny membrane. This shows that lateral diffusion is dependent on spine morphology and is restricted at the spine neck. These results demonstrate the importance of lateral diffusion in trafficking of AMPAR protein population and provide new insight into how spine structure can maintain synapse specificity by compartmentalizing lateral diffusion and therefore increasing the residence time of membrane proteins near individual synapses.