环境毒理
柯文山,熊治廷,柯世省,金则新.两个海州香薷种群根对Cu的吸收及Cu诱导的ATP酶活性差异[J].环境科学学报,2007,27(7):1214-1221
两个海州香薷种群根对Cu的吸收及Cu诱导的ATP酶活性差异
- Differences of Cu accumulation and Cu-induced ATPase activities in the roots of Cu resistant and control Elsholtzia haichowensis populations
- 基金项目:国家自然科学基金资助项目(No.30570322);浙江省自然科学基金资助项目(No.Y504256)
- 熊治廷
- 武汉大学资源与环境科学学院, 武汉 430079
- 摘要:通过水培实验,比较分析了分别来自湖北省铜绿山矿区和红安非矿区的海洲香薷种群根对铜的抗性和对Cu的吸收累积差异,同时应用微囊膜技术进行了ATPase的诱导和活性测定.结果发现,来自铜绿山种群植物的铜耐受性明显高于红安种群,在20μmol·L-1Cu处理时红安种群根尖开始变黑,生长明显受到抑制;而铜绿山种群在80μmol·L-1Cu处理时仍然能正常生长;在所有Cu处理中,铜绿山种群植物根的Cu含量明显低于红安种群.Cu诱导的ATPase活性在铜绿山种群根质膜有明显的变化,在1μmol·L-1Cu处理时,其活性显著增加,5μmol·L-1Cu处理时,其活性先到达高峰而后降低;而红安种群则没有出现Cu诱导的ATPase活性的升高,除了100μmol·L-1Cu明显降低了ATPase活性外,其它处理则没有显著的变化.在还原型谷光苷肽(GSH)存在的条件下,Cu诱导的ATPase活性在铜绿山种群中显著提高,且有明显的Cu浓度效应,而红安种群虽有提高但没有浓度效应.这些结果表明,矿区种群根细胞中可能存在Cu-ATPase,该酶在根的Cu吸收运输方面可能起重要的调节作用,从而使其具有较高的Cu抗性.
- Abstract:Two Elsholtzia haichowensis populations, one from an uncontaminated site (Hongan) and the other from a Cu mine site (Tonglushan) in Hubei province, were studied hydroponically for Cu resistance and root Cu accumulation. The Cu-induced ATPase activities in the roots of the two populations were also measured with a plasma membrane microsome method. The results showed that the Cu tolerance of the Tonglushan population was significantly higher than that of the Hongan population. Brown root tips were observed in the Hongan population under 20 μmol·L-1 Cu treatment and root growth was strongly inhibited by high Cu concentrations (≥20 μmol·L-1). In the Tonglushan population, however, root growth was promoted significantly under 5 and 20 μmol·L-1 Cu treatment and was not inhibited even under 80 μmol·L-1 Cu treatment. The root Cu concentration in the Tonglushan population was significantly lower than that in the Hongan population under any Cu treatment. The Cu-stimulated ATPase activity in the Tonglushan population increased significantly under 1 μmol·L-1 Cu treatment and increased up to 5 μmol·L-1 Cu followed by a decrease with increasing Cu concentration. However, no significant change of ATPase activity was observed in the Hongan population except for a significant decrease under 100 μmol·L-1 Cu treatment. When glutathione (GSH) was added to the solution, the Cu-stimulated ATPase activity increased with the increase of Cu concentration in the Tonglushan population, but not in the Hongan population. These results indicate that Cu-ATPase may be present in the root plasma membrane of the Tonglushan population, and play a role in copper resistance.
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