Department of Neurochemistry, Max-Planck-Institute for Brain Research, D-60528 Frankfurt/Main, Germany.
Biochem Biophys Res Commun. 2011 Sep 2;412(3):435-40. doi: 10.1016/j.bbrc.2011.07.110. Epub 2011 Jul 29.
Inhibitory glycine receptors (GlyRs) are densely packed in the postsynaptic membrane due to a high-affinity interaction of their β-subunits with the scaffolding protein gephyrin. Here, we used an affinity-based proteomic approach to identify the trafficking proteins Vacuolar Protein Sorting 35 (Vps35) and Neurobeachin (Nbea) as novel GlyR β-subunit (GlyRβ) interacting proteins in rat brain. Recombinant Vps35 and a central fragment of Nbea bound to the large intracellular loop of GlyRβ in glutathione-S-transferase pull-downs; in addition, Vps35 displayed binding to gephyrin. Immunocytochemical staining of spinal cord sections revealed Nbea immunoreactivity apposed to and colocalizing with marker proteins of inhibitory synapses. Our data are consistent with roles of Vps35 and Nbea in the retrieval and post-Golgi trafficking of synaptic GlyRs and possibly other neurotransmitter receptors.
抑制性甘氨酸受体（GlyRs）由于其β亚基与支架蛋白神经胶质纤维酸性蛋白（gephyrin）之间的高亲和力相互作用而密集地堆积在突触后膜上。在这里，我们使用基于亲和性的蛋白质组学方法，在大鼠脑中鉴定出了液泡蛋白分选 35（Vps35）和神经海滩蛋白（Nbea）作为新型 GlyRβ亚基（GlyRβ）相互作用蛋白。重组 Vps35 和 Nbea 的中心片段与谷胱甘肽 S-转移酶下拉中的 GlyRβ的大细胞内环结合；此外，Vps35 显示与神经胶质纤维酸性蛋白结合。脊髓切片的免疫细胞化学染色显示 Nbea 免疫反应与抑制性突触的标记蛋白并列和共定位。我们的数据与 Vps35 和 Nbea 在突触 GlyRs 和可能其他神经递质受体的回收和高尔基体后运输中的作用一致。
