Early Zn2+-induced effects on membrane potential account for primary heavy metal susceptibility in tolerant and sensitive Arabidopsis species
Early Zn2+-induced effects on membrane potential account for primary heavy metal susceptibility in tolerant and sensitive Arabidopsis species
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DOI：
10.1093/aob/mcs111
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发表时间：
2012-07-01
期刊：
影响因子：
4.2
通讯作者：
Ovecka, Miroslav
中科院分区：
文献类型：
--
作者：
Kenderesova, Lucia;Stanova, Andrea;Ovecka, Miroslav
植物根细胞对重金属的吸收依赖于质膜的电生理参数。在这项研究中，分析了根细胞质膜对金属离子诱导胁迫的早期反应。比较了三种不同的拟南芥属植物对重金属的不同适应策略：敏感的拟南芥和耐受的拟南芥和荒漠拟南芥。对植株的根生长速度、细胞耐受性、植株形态和根尖细胞死亡进行了测试。此外，还测定了成熟皮层根细胞的膜电位(E-M)和液体培养基中pH值的变化。在增加锌浓度的情况下，沙打旺和沙打旺的初级根生长明显好于沙打旺。培养液中锌离子浓度升高可引起E-M迅速变化。该反应具有物种特异性和浓度依赖性。在超高浓度长时间处理下，拟南芥表现出最高的质膜不敏感性和最高的存活率。对照植物能够有效地调节pH值，但在锌诱导的低pH条件下，植物的调节能力要弱得多。结果表明，植物对锌离子的早期反应模式相似，但在耐性和敏感的拟南芥中表现出不同的程度。结果表明，该菌对拟南美沙门氏菌敏感，对哈勒沙门氏菌和白背飞虱有较高的耐受性。质膜去极化在超积累植物沙打旺中最低，在沙打旺中最高。这表明，膜电压的快速变化是监测重金属影响的一个很好的工具。
Uptake of heavy metals by plant root cells depends on electro-physiological parameters of the plasma membrane. In this study, responses of the plasma membrane in root cells were analysed where early reactions to the metal ion-induced stress are localized. Three different Arabidopsis species with diverse strategies of their adaptation to heavy metals were compared: sensitive Arabidopsis thaliana and tolerant A. halleri and A. arenosa.Plants of A. thaliana Col-0 ecotype and plants of A. arenosa and A. halleri originating from natural metallicolous populations were exposed to high concentrations of Zn-2. Plants were tested for root growth rate, cellular tolerance, plant morphology and cell death in the root apex. In addition, the membrane potential (E-M) of mature cortical root cells and changes in the pH of the liquid culture media were measured.Primary roots of A. halleri and A. arenosa plants grew significantly better at increased Zn-2 concentrations than A. thaliana plants. Elevated Zn-2 concentrations in the culture medium induced rapid changes in E-M. The reaction was species-specific and concentration-dependent. Arabidopsis halleri revealed the highest insensitivity of the plasma membrane and the highest survival rate under prolonged treatment with extra-high concentrations. Plants were able to effectively adjust the pH in the control, but much less at Zn-2-induced lower pH.The results indicate a similar mode of early reaction to Zn-2, but with different extent in tolerant and sensitive species of Arabidopsis. The sensitivity of A. thaliana and a high tolerance of A. halleri and A. arenosa were demonstrated. Plasma membrane depolarization was lowest in the hyperaccumulator A. halleri and highest in A. thaliana. This indicates that rapid membrane voltage changes are an excellent tool to monitor the effects of heavy metals.