IRT1, an Arabidopsis transporter essential for iron uptake from the soil and for plant growth
IRT1, an Arabidopsis transporter essential for iron uptake from the soil and for plant growth
复制标题
DOI：
10.1105/tpc.001388
复制
发表时间：
2002-06-01
期刊：
影响因子：
11.6
通讯作者：
Curie, C
中科院分区：
文献类型：
--
作者：
Vert, G;Grotz, N;Curie, C
植物是大多数饮食中铁的主要来源，但铁的供应往往会限制植物的生长。在缺铁胁迫下，拟南芥根诱导二价阳离子转运蛋白IRT1的表达。在这里，我们提出了IRT1对于从土壤中吸收铁是必不可少的遗传证据。拟南芥IRT1基因敲除突变体是黄化的，在土壤中有严重的生长缺陷，导致死亡。这一缺陷被外源铁的应用所挽救。突变植物在低铁条件下不吸收铁，也不能积累其他二价阳离子。IRT1-绿色荧光蛋白融合，在培养细胞中瞬时表达，定位于质膜。我们还通过启动子：：β-葡萄糖醛酸酶分析和原位杂交表明，IRT1在根的外层细胞中表达，特别是在铁饥饿的反应中。这些结果清楚地表明，IRT1是缺铁条件下高亲和力金属摄取的主要转运体。
Plants are the principal source of iron in most diets, yet iron availability often limits plant growth. In response to iron deficiency, Arabidopsis roots induce the expression of the divalent cation transporter IRT1. Here, we present genetic evidence that IRT1 is essential for the uptake of iron from the soil. An Arabidopsis knockout mutant in IRT1 is chlorotic and has a severe growth defect in soil, leading to death. This defect is rescued by the exogenous application of iron. The mutant plants do not take up iron and fail to accumulate other divalent cations in low-iron conditions. IRT1-green fluorescent protein fusion, transiently expressed in culture cells, localized to the plasma membrane. We also show, through promoter::beta-glucuronidase analysis and in situ hybridization, that IRT1 is expressed in the external cell layers of the root, specifically in response to iron starvation. These results clearly demonstrate that IRT1 is the major transporter responsible for high-affinity metal uptake under iron deficiency.