Meier J, Vannier C, Sergé A, Triller A, Choquet D
Biologie Cellulaire de la Synapse N&P INSERM U497, Ecole Normale Supérieure 46, rue d'Ulm 75005, Paris, France.
Nat Neurosci. 2001 Mar;4(3):253-60. doi: 10.1038/85099.
Variations in receptor number at a given synapse are known to contribute to synaptic plasticity, but methods used to establish this idea usually do not allow for the determination of the dynamics of these phenomena. We used single-particle tracking to follow in real time, on the cell surface, movements of the glycine receptor (GlyR) with or without the GlyR stabilizing protein gephyrin. GlyR alternated within seconds between diffusive and confined states. In the absence of gephyrin, GlyR were mostly freely diffusing. Gephyrin induced long confinement periods spatially associated with submembranous clusters of gephyrin. However, even when most receptors were stabilized, they still frequently made transitions through the diffusive state. These data show that receptor number in a cluster results from a dynamic equilibrium between the pools of stabilized and freely mobile receptors. Modification of this equilibrium could be involved in regulation of the number of receptors at synapses.
已知给定突触处受体数量的变化会导致突触可塑性，但用于证实这一观点的方法通常无法确定这些现象的动态变化。我们使用单粒子追踪技术，在细胞表面实时追踪有无甘氨酸受体（GlyR）稳定蛋白桥连蛋白情况下甘氨酸受体（GlyR）的运动。GlyR在数秒内会在扩散状态和受限状态之间交替。在没有桥连蛋白的情况下，GlyR大多自由扩散。桥连蛋白诱导出与桥连蛋白膜下簇在空间上相关的长时间受限期。然而，即使大多数受体被稳定下来，它们仍频繁地通过扩散状态进行转换。这些数据表明，簇中受体数量是由稳定受体池和自由移动受体池之间的动态平衡产生的。这种平衡的改变可能参与突触处受体数量的调节。
