Molecular characterization of a broad selectivity neutral solute channel
Molecular characterization of a broad selectivity neutral solute channel
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DOI：
10.1074/jbc.273.38.24737
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发表时间：
1998-09-18
影响因子：
4.8
通讯作者：
Hediger, MA
中科院分区：
文献类型：
--
作者：
Tsukaguchi, H;Shayakul, C;Hediger, MA
在所有活细胞中，溶质和水穿过细胞膜的运动的协调对于渗透平衡至关重要。目前的概念是，这些过程具有不同的生物物理性质。在这里，我们报告的表达克隆的肝脏cDNA编码一个独特的混杂溶质通道（AQP 9），赋予高渗透性的溶质和水。AQP 9以根皮素和汞敏感的方式介导多种不带电溶质的通过，包括脲、多元醇、嘌呤和嘧啶，而氨基酸、环状糖、Na+、K+、Cl-和去质子化的单羧酸盐被排除在外。AQP 9的性质定义了水通道蛋白的主要内在蛋白家族的一个新的进化分支，并描述了一种以前未知的机制，通过该机制，多种溶质和水可以通过单个孔，从而能够以最小的渗透扰动快速细胞摄取或排出代谢物。
In all living cells, coordination of solute and water movement across cell membranes is of critical importance for osmotic balance. The current concept is that these processes are of distinct biophysical nature. Here we report the expression cloning of a Liver cDNA encoding a unique promiscuous solute channel (AQP9) that confers high permeability for both solutes and water. AQP9 mediates passage of a wide variety of non-charged solutes including carbamides, polyols, purines, and pyrimidines in a phloretin- and mercury-sensitive manner, whereas amino acids, cyclic sugars, Na+, K+, Cl-, and deprotonated monocarboxylates are excluded. The properties of AQP9 define a new evolutionary branch of the major intrinsic protein family of aquaporin proteins and describe a previously unknown mechanism by which a large variety of solutes and water can pass through a single pore, enabling rapid cellular uptake or exit of metabolites with minimal osmotic perturbation.