Modular Design of the Selectivity Filter Pore Loop in a Novel Family of Prokaryotic 'Inward Rectifier' (NirBac) channels.
Modular Design of the Selectivity Filter Pore Loop in a Novel Family of Prokaryotic 'Inward Rectifier' (NirBac) channels.
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DOI：
10.1038/srep15305
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发表时间：
2015-10-16
影响因子：
4.6
通讯作者：
Tucker SJ
中科院分区：
文献类型：
--
作者：
Zubcevic L;Wang S;Bavro VN;Lee SJ;Nichols CG;Tucker SJ
钾通道具有模块化设计，具有不同的结构和功能域;特别是高度保守的孔环序列，决定了它们的离子选择性。我们现在报告的功能特性的一组新的功能非选择性成员的原核'内向整流'亚家族的K+通道。这些通道共享真核生物和原核生物Kir/KirBac通道的所有关键结构域，但具有与任何其他已知离子选择性过滤器无关的独特孔环选择性过滤器序列。这些“NirBac”通道的显着不寻常的架构定义了一个新的功能性非选择性离子通道家族，也提供了重要的见解离子通道的模块化设计，以及在这个超家族的四聚体阳离子通道的离子选择性的演变。
Potassium channels exhibit a modular design with distinct structural and functional domains; in particular, a highly conserved pore-loop sequence that determines their ionic selectivity. We now report the functional characterisation of a novel group of functionally non-selective members of the prokaryotic ‘inward rectifier’ subfamily of K+ channels. These channels share all the key structural domains of eukaryotic and prokaryotic Kir/KirBac channels, but instead possess unique pore-loop selectivity filter sequences unrelated to any other known ionic selectivity filter. The strikingly unusual architecture of these ‘NirBac’ channels defines a new family of functionally non-selective ion channels, and also provides important insights into the modular design of ion channels, as well as the evolution of ionic selectivity within this superfamily of tetrameric cation channels.