Bignami F, Camus G, Marchand S, Bailly L, Stetzkowski-Marden F, Cartaud J
Institut Jacques-Monod, CNRS, Universités Paris 6, France.
J Physiol Paris. 1998 Jun-Aug;92(3-4):177-81. doi: 10.1016/s0928-4257(98)80006-5.
In this study we have investigated the intracellular routing of two major components of the postsynaptic membrane in Torpedo electrocytes, the nicotinic acetylcholine receptor and the extrinsic 43 kDa protein rapsyn, and of a protein from the non-innervated membrane, the Na+,K+ ATPase. We isolated subpopulations of post-Golgi vesicles (PGVs) enriched either in AChR or in Na+,K+ ATPase. Rapsyn was associated to AChR-containing PGVs suggesting that both AChR and rapsyn are targeted to intracellular organelles in the secretory pathway before delivery to the postsynaptic membrane. In vitro assays further show that rapsyn-containing PVGs do bind more efficiently to microtubules compared to Na+,K+ ATPase-enriched PVGs. These data provide evidence in favor of the contribution of the secretory pathway to the delivery of synaptic components.
在本研究中，我们研究了电鳐电细胞中突触后膜的两个主要成分——烟碱型乙酰胆碱受体和外在43 kDa蛋白rapsyn，以及来自非神经支配膜的一种蛋白——Na⁺,K⁺ ATP酶的细胞内转运途径。我们分离了富含乙酰胆碱受体或Na⁺,K⁺ ATP酶的高尔基体后囊泡（PGV）亚群。rapsyn与含有乙酰胆碱受体的PGV相关，这表明乙酰胆碱受体和rapsyn在被递送至突触后膜之前，在分泌途径中都被靶向到细胞内细胞器。体外实验进一步表明，与富含Na⁺,K⁺ ATP酶的PGV相比，含有rapsyn的PGV与微管的结合效率更高。这些数据为分泌途径对突触成分传递的贡献提供了证据。
