Mourot Alexandre, Rodrigo J, Bertrand Sonia, Bertrand Daniel, Goeldner Maurice, Kotzyba-Hibert Florence
UMR 7514 CNRS, Université Louis Pasteur Strasbourg, BP 24, 67401 Illkirch Cedex, France.
J Mol Neurosci. 2006;30(1-2):13-4. doi: 10.1385/JMN:30:1:13.
The nicotinic acetylcholine receptor (nAChR) from fish electric organs and vertebrate neuromuscular junctions is a well-characterized transmembrane allosteric protein, composed of four polypeptide chains assembled into a heterologous pentamer alpha2betagammadelta, which carries ACh-binding sites and contains cation-selective channel-forming elements. Topographical mapping of residues contributing to the ligand-binding domain (LBD) of Torpedo nAChR was achieved with different site-directed antagonist or agonist probes. Over two decades of biochemical investigation led to the identification of three discontinuous domains on alpha subunits, with additional residues on gamma and delta subunits (Kotzyba- Hibert et al., 2004). This six binding-segment-domain model fits quite nicely with the three-dimensional positioning of the homologous residues in AChbinding protein (Brejc et al., 2001). However, little is known about the structural dynamics of the functioning receptor.
来自鱼类电器官和脊椎动物神经肌肉接头的烟碱型乙酰胆碱受体（nAChR）是一种特征明确的跨膜变构蛋白，由四条多肽链组装成异源五聚体α2βγδ，它带有乙酰胆碱结合位点并包含阳离子选择性通道形成元件。通过不同的定点拮抗剂或激动剂探针，实现了对电鳐nAChR配体结合结构域（LBD）中贡献残基的拓扑图谱绘制。二十多年的生化研究导致在α亚基上鉴定出三个不连续结构域，γ和δ亚基上还有其他残基（科齐巴 - 希伯特等人，2004年）。这种六个结合片段结构域模型与乙酰胆碱结合蛋白中同源残基的三维定位非常吻合（布雷伊克等人，2001年）。然而，对于功能受体的结构动力学知之甚少。
