Substrate-induced conformational dynamics of the dopamine transporter
Substrate-induced conformational dynamics of the dopamine transporter
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DOI：
10.1038/s41467-019-10449-w
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发表时间：
2019-06-20
影响因子：
16.6
通讯作者：
Loland, Claus J.
中科院分区：
文献类型：
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作者：
Nielsen, Anne Kathrine;Moller, Ingvar R.;Loland, Claus J.
多巴胺转运体是神经递质钠同向转运体（nss）的一员，它负责通过Na+驱动的神经递质从细胞外空间的再摄取来终止神经传递。迄今为止，阐明与输运机制有关的协调构象重排的实验证据有限。在这里，我们利用氢-氘交换质谱法探讨了野生型黑腹果蝇多巴胺转运体的全局Na+和多巴胺诱导的构象动力学。我们确定了Na+和多巴胺在转运体的特定区域诱导的变化，表明它们参与了蛋白质的构象转变。此外，我们在转运体的几个区域检测到配体依赖的螺旋拉伸缓慢合作波动，这可能是一种辅助转运体功能的分子机制。我们的研究结果揭示了与多巴胺转运体交替通路模型相关的状态依赖性构象变化，为理解nss功能的分子机制提供了一个框架。
The dopamine transporter is a member of the neurotransmitter:sodium symporters (NSSs), which are responsible for termination of neurotransmission through Na+-driven reuptake of neurotransmitter from the extracellular space. Experimental evidence elucidating the coordinated conformational rearrangements related to the transport mechanism has so far been limited. Here we probe the global Na+- and dopamine-induced conformational dynamics of the wild-type Drosophila melanogaster dopamine transporter using hydrogen-deuterium exchange mass spectrometry. We identify Na+- and dopamine-induced changes in specific regions of the transporter, suggesting their involvement in protein conformational transitions. Furthermore, we detect ligand-dependent slow cooperative fluctuations of helical stretches in several domains of the transporter, which could be a molecular mechanism that assists in the transporter function. Our results provide a framework for understanding the molecular mechanism underlying the function of NSSs by revealing detailed insight into the state-dependent conformational changes associated with the alternating access model of the dopamine transporter.