A subgroup of plant aquaporins facilitate the bi-directional diffusion of As(OH)3 and Sb(OH)3 across membranes.
A subgroup of plant aquaporins facilitate the bi-directional diffusion of As(OH)3 and Sb(OH)3 across membranes.
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DOI：
10.1186/1741-7007-6-26
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发表时间：
2008-06-10
期刊：
影响因子：
5.4
通讯作者：
Jahn TP
中科院分区：
文献类型：
--
作者：
Bienert GP;Thorsen M;Schüssler MD;Nilsson HR;Wagner A;Tamás MJ;Jahn TP
砷是一种有毒且含量丰富的类金属，通过饮用水和食物链危害人类健康。砷在环境中最常见的形式是砷酸盐（As（V））和亚砷酸盐（As（III））。As（V）是一种非功能性磷酸盐类似物，通过植物磷酸盐转运蛋白进入食物链。在细胞内，As（V）被还原为As（III），随后被挤出或分隔。虽然知道很多关于As（III）在微生物和哺乳动物中的运输和处理，运输系统的As（III）尚未在植物中的特点。在这里，我们表明，Nodulin 26-like内在蛋白（NIPs）AtNIP 5;1和AtNIP 6;1从拟南芥，OsNIP 2;1和OsNIP 3;2从水稻，LjNIP 5;1和LjNIP 6;1从百脉根是双向As（III）通道。这些NIPs的表达敏化酵母细胞As（III）和锑（Sb（III）），和直接运输试验证实了它们的能力，以促进As（III）跨细胞膜运输。在含有As（V）的培养基上，相同NIP的表达改善了酵母的生长，这可能是由于As（III）流出增加。此外，我们的数据提供的证据表明，NIP可以区分高度相似的基板，他们可能有不同的偏好在运输方向。一个亚组的As（III）的渗透通道，在系统发育树中的组在一起需要在酵母中的功能表达的N-末端截短。这是植物As（III）运输系统的第一个分子鉴定，我们建议通过NIPs的类金属运输是一个保守的和古老的功能。我们的观察是潜在的非常重要的改善修复和耐受性的植物，并可能提供一个关键的低砷作物的粮食生产的发展。
Arsenic is a toxic and highly abundant metalloid that endangers human health through drinking water and the food chain. The most common forms of arsenic in the environment are arsenate (As(V)) and arsenite (As(III)). As(V) is a non-functional phosphate analog that enters the food chain via plant phosphate transporters. Inside cells, As(V) becomes reduced to As(III) for subsequent extrusion or compartmentation. Although much is known about As(III) transport and handling in microbes and mammals, the transport systems for As(III) have not yet been characterized in plants. Here we show that the Nodulin26-like Intrinsic Proteins (NIPs) AtNIP5;1 and AtNIP6;1 from Arabidopsis thaliana, OsNIP2;1 and OsNIP3;2 from Oryza sativa, and LjNIP5;1 and LjNIP6;1 from Lotus japonicus are bi-directional As(III) channels. Expression of these NIPs sensitized yeast cells to As(III) and antimonite (Sb(III)), and direct transport assays confirmed their ability to facilitate As(III) transport across cell membranes. On medium containing As(V), expression of the same NIPs improved yeast growth, probably due to increased As(III) efflux. Our data furthermore provide evidence that NIPs can discriminate between highly similar substrates and that they may have differential preferences in the direction of transport. A subgroup of As(III) permeable channels that group together in a phylogenetic tree required N-terminal truncation for functional expression in yeast. This is the first molecular identification of plant As(III) transport systems and we propose that metalloid transport through NIPs is a conserved and ancient feature. Our observations are potentially of great importance for improved remediation and tolerance of plants, and may provide a key to the development of low arsenic crops for food production.
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影响因子：
5.2
作者：
Cabello-Hurtado, F;Ramos, J
通讯作者：
Ramos, J
影响因子：
14.9
作者：
Benson DA;Cavanaugh M;Clark K;Karsch-Mizrachi I;Ostell J;Pruitt KD;Sayers EW
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Sayers EW
影响因子：
11.6
作者：
Guenther, JF;Chanmanivone, N;Roberts, DM
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Roberts, DM
影响因子：
11.6
作者：
Johansson, I;Karlsson, M;Kjellbom, P
通讯作者：
Kjellbom, P
影响因子：
10.4
作者：
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Vahter, M