Cytochrome c oxydase subunit I gene is up-regulated by cadmium in freshwater and marine bivalves
Cytochrome c oxydase subunit I gene is up-regulated by cadmium in freshwater and marine bivalves
复制标题
DOI：
10.1007/s10534-005-5671-9
复制
发表时间：
2006-06-01
期刊：
影响因子：
3.5
通讯作者：
Bourdineaud, Jean-Paul
中科院分区：
文献类型：
--
作者：
Achard-Joris, Maud;Gonzalez, Patrice;Bourdineaud, Jean-Paul
线粒体电子传递链的抑制和活性氧(ROS)的产生是镉中毒的根源之一。为了了解镉对线粒体的影响，我们重点研究了编码细胞色素C氧化酶亚基I(呼吸链复合体IV)的Coxi基因的表达。应用实时荧光定量聚合酶链式反应技术，研究了两种淡水双壳贝类(河蚌和多态牡蛎)和一种海洋双壳贝类(二倍体或三倍体长牡蛎)Coxi基因的表达。在受控实验室条件下，将双壳贝类暴露于0.13亩Cd~(2+)和15.3亩M~(2+)中10天或14天。我们发现在这三种软体动物中，Cd上调了Coxi基因的表达。已知具有抗氧化特性的锌对Coxi基因的表达没有影响。在Cd和Zn存在的情况下，Coxi基因在每个物种中的诱导性都低于单一Cd暴露后的水平；这一结果不能完全用Cd积累的减少来解释。Cd诱导的Coxi基因在三倍体牡蛎中是二倍体牡蛎的4.8倍，这表明三倍体可能影响动物对Cd污染的反应。
Inhibition of the mitochondrial electron transfer chain and induction of reactive oxygen species (ROS) production are one of the roots of cadmium (Cd) toxicity. To appreciate the impact of Cd on mitochondria, we focused on the expression of CoxI gene which encodes the subunit I of the Cytochrome c oxidase (complex IV of the respiratory chain). CoxI gene expression was studied by real-time quantitative PCR in three species: two freshwater bivalves (Corbicula fluminea and Dreissena polymorpha) and one marine bivalve (diploid or triploid Crassostrea gigas). Bivalves were exposed for 10 or 14 days to 0.13 mu M Cd2+ and 15.3 mu M Zn2+ in controlled laboratory conditions. We demonstrate that in the three mollusk species CoxI gene was up-regulated by Cd. Zinc (Zn), which is known to have antioxidant properties, had no effect on CoxI gene expression. In the presence of Cd and Zn, CoxI gene inducibility was lower than after a single Cd exposure, in each species; result that could not be fully explained by a decreased Cd accumulation. CoxI gene induction by Cd was 4.8-fold higher in triploid oysters than in diploid ones, indicating a possible influence of triploidy on animal responses to Cd contamination.