Ion permeability of the nuclear pore complex and ion-induced macromolecular permeation as studied by scanning electrochemical and fluorescence microscopy.
Ion permeability of the nuclear pore complex and ion-induced macromolecular permeation as studied by scanning electrochemical and fluorescence microscopy.
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DOI：
10.1021/ac403607s
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发表时间：
2014-02-18
影响因子：
7.4
通讯作者：
Amemiya, Shigeru
中科院分区：
文献类型：
--
作者：
Kim, Jiyeon;Izadyar, Anahita;Shen, Mei;Ishimatsu, Ryoichi;Amemiya, Shigeru
将治疗性大分子和纳米材料有效输送到细胞核中对于基因治疗和纳米医学至关重要。然而，核细胞质分子运输受到核孔复合物 (NPC) 的严格调控，核孔复合物具有基于苯丙氨酸和甘氨酸重复序列的疏水运输屏障。在此，我们应用扫描电化学显微镜（SECM）定量研究NPC对具有广泛疏水性的小探针离子的渗透性，作为其与运输屏障的疏水相互作用的量度。通过使用基于两种不混溶电解质溶液之间的微移液器或纳米移液器支持的界面的离子选择性 SECM 尖端，可以对氧化还原非活性探针离子进行电流检测。通过 SECM 成功测量了 NPC 的极高离子渗透性并进行了理论分析。该分析表明，NPC 的离子渗透性由纳米孔的尺寸和密度决定，传输势垒对传输的离子没有显着影响。重要的是，弱离子-势垒相互作用在足够高浓度的极度疏水性离子（即四苯砷鎓和全氟丁基磺酸盐）下变得显着，以使NPC渗透到天然不可渗透的大分子中。通过使用荧光显微镜研究 NPC 的离子诱导透化对大分子运输途径和模式的依赖性，以更深入地了解 NPC 的门控机制，作为新运输模型的基础。
Efficient delivery of therapeutic macromolecules and nanomaterials into the nucleus is imperative for gene therapy and nanomedicine. Nucleocytoplasmic molecular transport, however, is tightly regulated by the nuclear pore complex (NPC) with the hydrophobic transport barriers based on phenylalanine and glycine repeats. Herein, we apply scanning electrochemical microscopy (SECM) to quantitatively study the permeability of the NPCs to small probe ions with a wide range of hydrophobicity as a measure of their hydrophobic interactions with the transport barriers. Amperometric detection of the redox-inactive probe ions is enabled by using the ion-selective SECM tips based on the micropipet- or nanopipet-supported interfaces between two immiscible electrolyte solutions. The remarkably high ion permeability of the NPCs is successfully measured by SECM and theoretically analyzed. This analysis demonstrates that the ion permeability of the NPCs is determined by the dimensions and density of the nanopores without a significant effect of the transport barriers on the transported ions. Importantly, the weak ion–barrier interactions become significant at sufficiently high concentrations of extremely hydrophobic ions, i.e., tetraphenylarsonium and perfluorobutylsulfonate, to permeabilize the NPCs to naturally impermeable macromolecules. Dependence of ion-induced permeabilization of the NPC on the pathway and mode of macromolecular transport is studied by using fluorescence microscopy to obtain deeper insights into the gating mechanism of the NPC as the basis of a new transport model.
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影响因子：
15
作者：
Jing P;Rodgers PJ;Amemiya S
通讯作者：
Amemiya S
影响因子：
7.4
作者：
Guo, JD;Amemiya, S
通讯作者：
Amemiya, S
影响因子：
56.9
作者：
Frey, Steffen;Richter, Ralf P.;Goerlich, Dirk
通讯作者：
Goerlich, Dirk
影响因子：
15
作者：
Kim, Jiyeon;Izadyar, Anahita;Nioradze, Nikoloz;Amemiya, Shigeru
通讯作者：
Amemiya, Shigeru
DOI：
10.1083/jcb.104.2.189
发表时间：
1987-02
期刊：
The Journal of cell biology
影响因子：
--
作者：
Finlay DR;Newmeyer DD;Price TM;Forbes DJ
通讯作者：
Forbes DJ