NMR structures of the transmembrane domains of the α4β2 nAChR
NMR structures of the transmembrane domains of the α4β2 nAChR
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DOI：
10.1016/j.bbamem.2012.02.008
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发表时间：
2012-05-01
影响因子：
3.4
通讯作者：
Tang, Pei
中科院分区：
文献类型：
--
作者：
Bondarenko, Vasyl;Mowrey, David;Tang, Pei
α 4 β 2烟碱乙酰胆碱受体（nAChR）是脑中nAChR的主要异聚体亚型，其与许多神经病症有关。目前，专门针对α 4 β 2和其他神经元nAChR的结构信息有限。在这项研究中，我们确定了跨膜（TM）结构域的α 4和β 2亚基在十二烷基二甲基氧化胺（LDAO）胶束使用溶液NMR光谱。NMR实验和尺寸排阻色谱-多角度光散射（SEC-MALS）分析表明，Phi 4和β 2的TM结构域相互作用，在LDAO胶束中自发形成五聚体组装体. Na+通量测定显示α 4 β 2在脂质囊泡中形成Na+渗透通道。Na+通过α 4 β 2通道的流出以时间依赖性方式减少囊泡内钠绿色（TM）荧光，这在没有掺入α 4 β 2的囊泡中没有观察到。该研究提供了对α 4 β 2 nAChR的TM结构域的结构洞察。它提供了一个有价值的结构框架，合理化广泛的生化数据收集以前的α 4 β 2 nAChR和设计新的治疗调节剂。(C)2012 Elsevier B. V.保留所有权利。
The alpha 4 beta 2 nicotinic acetylcholine receptor (nAChR) is the predominant heteromeric subtype of nAChRs in the brain, which has been implicated in numerous neurological conditions. The structural information specifically for the alpha 4 beta 2 and other neuronal nAChRs is presently limited. In this study, we determined structures of the transmembrane (TM) domains of the alpha 4 and beta 2 subunits in lauryldimethylamine-oxide (LDAO) micelles using solution NMR spectroscopy. NMR experiments and size exclusion chromatography-multi-angle light scattering (SEC-MALS) analysis demonstrated that the TM domains of Phi 4 and beta 2 interacted with each other and spontaneously formed pentameric assemblies in the LDAO micelles. The Na+ flux assay revealed that alpha 4 beta 2 formed Na+ permeable channels in lipid vesicles. Efflux of Na+ through the alpha 4 beta 2 channels reduced intra-vesicle Sodium Green (TM) fluorescence in a time-dependent manner that was not observed in vesicles without incorporating alpha 4 beta 2. The study provides structural insight into the TM domains of the alpha 4 beta 2 nAChR. It offers a valuable structural framework for rationalizing extensive biochemical data collected previously on the alpha 4 beta 2 nAChR and for designing new therapeutic modulators. (C) 2012 Elsevier B.V. All rights reserved.