Subcellular Cd distribution and its correlation with antioxidant enzymatic activities in wheat (Triticum aestivum) roots
Subcellular Cd distribution and its correlation with antioxidant enzymatic activities in wheat (Triticum aestivum) roots
复制标题
DOI：
10.1016/j.ecoenv.2010.12.006
复制
发表时间：
2011-05-01
影响因子：
6.8
通讯作者：
Zhu Xiangdong
中科院分区：
文献类型：
--
作者：
Li Dandan;Zhou Dongmei;Zhu Xiangdong
通过对小麦根匀浆进行差速离心，获得了小麦根中镉的亚细胞分配，以量化镉在5个亚细胞组分中的含量，即富镉颗粒（MRG）、细胞碎片、细胞器、热变性蛋白（HDP）和热稳定蛋白（HSP）。结果表明，Cd胁迫（0.01 ~ 9.68 μ M） 72 h后，脱毒部位（MRG + HSP）的相对Cd分布随着Cd的增加而减少，而金属敏感部位（HDP +细胞器）的相对Cd分布则增加。因此，超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的含量降低。此外，还观察到总抗氧化能力（a - toc）的增加和丙二醛（MDA）的轻微下降。相对根伸长（RRL）和CAT与cd敏感组分呈极显著相关。这些结果表明，镉对小麦根系的毒性很大程度上取决于亚细胞镉的分布。(C) 2010爱思唯尔公司版权所有。
The subcellular partitioning of Cd in wheat root was obtained by differential centrifugation of root homogenates to quantify the amounts of Cd associated with five operationally defined subcellular fractions, namely Cd-rich granule (MRG), cellular debris, organelles, heat-denatured protein (HDP), and heat-stable protein (HSP). Their correlations were investigated with the changes in antioxidant enzymatic activities under Cd stress (0.01-9.68 mu M) for 72 h. The results showed that the relative Cd distribution in detoxified fractions (MRG + HSP) was decreased with increasing [Cd], but in metal-sensitive fractions (HDP + organelles) was increased. Consequently, the content of superoxide dismutase (SOD) and catalase (CAT) was decreased. Additionally, an increase of the total antioxidant capacity (A-TOC) and a slight decrease of malondialdehyde (MDA) were also observed. Interestingly, the relative root elongation (RRL) and CAT were significantly correlated with the Cd-sensitive fractions. These results suggest that the Cd toxicity to wheat roots strongly depends on the subcellular Cd distribution. (C) 2010 Elsevier Inc. All rights reserved.