Molecular basis for cation selectivity in claudin-2-based paracellular pores: identification of an electrostatic interaction site.
Molecular basis for cation selectivity in claudin-2-based paracellular pores: identification of an electrostatic interaction site.
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DOI：
10.1085/jgp.200810154
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发表时间：
2009-01
期刊：
影响因子：
--
通讯作者：
Coalson RD
中科院分区：
文献类型：
--
作者：
Yu AS;Cheng MH;Angelow S;Günzel D;Kanzawa SA;Schneeberger EE;Fromm M;Coalson RD
上皮细胞中的细胞旁离子转运是由密蛋白家族成员形成的孔介导的。人们对离子渗透穿过密蛋白孔的选择性程度和分子机制知之甚少。通过在诱导型启动子的控制下，在高抗性 Madin-Darby 犬肾细胞中表达高电导密蛋白亚型（claudin-2），我们能够定量密蛋白孔渗透性。发现 Claudin-2 孔狭窄、充满液体且具有阳离子选择性。电荷选择性是通过部分脱水渗透阳离子与天冬氨酸 65 侧链羧基形成的孔内带负电位点的静电相互作用介导的。因此，细胞旁孔利用孔内静电结合位点来实现具有高度电荷选择性的高电导率。
Paracellular ion transport in epithelia is mediated by pores formed by members of the claudin family. The degree of selectivity and the molecular mechanism of ion permeation through claudin pores are poorly understood. By expressing a high-conductance claudin isoform, claudin-2, in high-resistance Madin-Darby canine kidney cells under the control of an inducible promoter, we were able to quantitate claudin pore permeability. Claudin-2 pores were found to be narrow, fluid filled, and cation selective. Charge selectivity was mediated by the electrostatic interaction of partially dehydrated permeating cations with a negatively charged site within the pore that is formed by the side chain carboxyl group of aspartate-65. Thus, paracellular pores use intrapore electrostatic binding sites to achieve a high conductance with a high degree of charge selectivity.
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影响因子：
2.4
作者：
BARRY, PH;DIAMOND, JM
通讯作者：
DIAMOND, JM
影响因子：
5.5
作者：
Colegio, OR;Van Itallie, C;Anderson, JM
通讯作者：
Anderson, JM
影响因子：
3.3
作者：
Graf, P;Nitzan, A;Coalson, RD
通讯作者：
Coalson, RD
影响因子：
5.5
作者：
Angelow, S;Kim, KJ;Yu, ASL
通讯作者：
Yu, ASL
影响因子：
3.3
作者：
Cheng, HY;Coalson, RD
通讯作者：
Coalson, RD