Specific aquaporins facilitate the diffusion of hydrogen peroxide across membranes
Specific aquaporins facilitate the diffusion of hydrogen peroxide across membranes
复制标题
DOI：
10.1074/jbc.m603761200
复制
发表时间：
2007-01-12
影响因子：
4.8
通讯作者：
Jahn, Thomas P.
中科院分区：
文献类型：
--
作者：
Bienert, Gerd P.;Moller, Anders L. B.;Jahn, Thomas P.
需氧生物的新陈代谢不断产生活性氧。尽管这些化合物具有潜在的毒性，但它们也在信号传导中发挥作用。信号化合物的一个重要特征是它们在不同隔室之间移动的能力，例如，G.穿过细胞膜。在这里，我们提出的证据表明，水通道蛋白可以通道过氧化氢（H2 O2）。24个水通道蛋白从植物和哺乳动物中筛选的5个酵母菌株对氧化应激的敏感性不同。人AQP 8和植物拟南芥TIP 1;1和TIP 1; 2在酵母中的表达降低了H2 O2存在下的生长和存活。水通道蛋白介导的H2 O2扩散的进一步证据是通过使用细胞内活性氧敏感的荧光染料的完整酵母细胞的荧光测定获得的。应用银离子（Ag+），它阻止水通道蛋白介导的水扩散的快速动力学肿胀测定，也逆转了水通道蛋白依赖的生长抑制和H2 O2诱导的荧光。我们的研究结果提出了第一个分子遗传学证据的H2 O2通过水通道蛋白家族的特定成员的扩散。
The metabolism of aerobic organisms continuously produces reactive oxygen species. Although potentially toxic, these compounds also function in signaling. One important feature of signaling compounds is their ability to move between different compartments, e. g. to cross membranes. Here we present evidence that aquaporins can channel hydrogen peroxide (H2O2). Twenty-four aquaporins from plants and mammals were screened in five yeast strains differing in sensitivity toward oxidative stress. Expression of human AQP8 and plant Arabidopsis TIP1;1 and TIP1; 2 in yeast decreased growth and survival in the presence of H2O2. Further evidence for aquaporin-mediated H2O2 diffusion was obtained by a fluorescence assay with intact yeast cells using an intracellular reactive oxygen species-sensitive fluorescent dye. Application of silver ions (Ag+), which block aquaporin-mediated water diffusion in a fast kinetics swelling assay, also reversed both the aquaporin-dependent growth repression and the H2O2-induced fluorescence. Our results present the first molecular genetic evidence for the diffusion of H2O2 through specific members of the aquaporin family.