Recent advances in imaging technology have highlighted that scaffold proteins and receptors are arranged in sub-synaptic nanodomains. The synaptic MAGUK scaffold protein MPP2 is a component of AMPA receptor-associated protein complexes and also binds to the synaptic cell adhesion molecule SynCAM1. Using super-resolution imaging, we now show that MPP2 and SynCAM1 are situated at the periphery of the postsynaptic density. In order to explore MPP2-associated protein complexes, we used a quantitative comparative mass spectrometry approach and identified multiple GABA A receptor subunits among the novel synaptic MPP2 interactors. We further show that GABAA receptors are found together with MPP2 in a subset of dendritic spines and thus highlight MPP2 as a scaffold molecule capable of acting as an adaptor molecule that links peripheral synaptic elements critical for inhibitory regulation to central structures at the PSD of glutamatergic synapses.

中文翻译：

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突触后的MAGUK支架蛋白MPP2组织了一个独特的相互作用组，该相互作用组在兴奋性突触的周围结合了GABAA受体

成像技术的最新进展突出了支架蛋白和受体排列在突触下的纳米域中。突触的MAGUK支架蛋白MPP2是AMPA受体相关蛋白复合物的一个组成部分，还与突触细胞粘附分子SynCAM1结合。使用超分辨率成像，我们现在显示MPP2和SynCAM1位于突触后密度的外围。为了探索与MPP2相关的蛋白质复合物，我们使用了定量比较质谱方法，并在新型突触MPP2相互作用子中鉴定了多个GABA A受体亚基。