Adhesion proteins play crucial roles at synapses, not only by providing a physical trans-synaptic linkage between axonal and dendritic membranes, but also by connecting to functional elements including the pre-synaptic neurotransmitter release machinery and post-synaptic receptors. To mediate these functions, adhesion proteins must be organized on the neuronal surface in a precise and controlled manner. Recent studies have started to describe the mobility, nanoscale organization, and turnover rate of key synaptic adhesion molecules including cadherins, neurexins, neuroligins, SynCAMs, and LRRTMs, and show that some of these proteins are highly mobile in the plasma membrane while others are confined at sub-synaptic compartments, providing evidence for different regulatory pathways. In this review article, we provide a biophysical view of the diffusional trapping of adhesion molecules at synapses, involving both extracellular and intracellular protein interactions. We review the methodology underlying these measurements, including biomimetic systems with purified adhesion proteins, means to perturb protein expression or function, single molecule imaging in cultured neurons, and analytical models to interpret the data. This article is part of the special issue entitled 'Mobility and trafficking of neuronal membrane proteins'.

中文翻译：

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突触粘附分子的膜运输基础的生物物理机制。

粘附蛋白不仅在轴突和树突膜之间提供物理的跨突触连接，而且还通过与包括突触前神经递质释放机制和突触后受体在内的功能元件连接，在突触中发挥关键作用。为了介导这些功能，粘附蛋白必须以精确和受控的方式组织在神经元表面上。最近的研究已经开始描述关键突触粘附分子（包括钙黏着蛋白，神经毒素，神经胶蛋白，SynCAMs和LRRTMs）的迁移率，纳米级组织和周转率，并显示其中一些蛋白在质膜中具有很高的移动性，而另一些则被限制在质膜中。在突触下的隔室中，为不同的调节途径提供了证据。在这篇评论文章中，我们提供了突触中粘附分子的扩散捕获的生物物理视图，涉及细胞外和细胞内蛋白质的相互作用。我们回顾了这些测量基础的方法，包括具有纯化的粘附蛋白的仿生系统，干扰蛋白表达或功能的手段，培养的神经元中的单分子成像以及解释数据的分析模型。本文是题为“神经元膜蛋白的移动性和运输”的特刊的一部分。培养的神经元中的单分子成像，以及用于解释数据的分析模型。本文是题为“神经元膜蛋白的移动性和运输”的特刊的一部分。培养的神经元中的单分子成像，以及用于解释数据的分析模型。本文是题为“神经元膜蛋白的移动性和运输”的特刊的一部分。