The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control, College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Sep;25(27):27639-27649. doi: 10.1007/s11356-018-2817-1. Epub 2018 Jul 28.
Cytochrome c (CYTc) is one of the redox-active molecules responsible for electron transport in plant mitochondria. It is important in the interaction of metal ions with mitochondrial proteome, it is also essential for insights into electron transport during oxidative stress. This study focused on the clarification of interactions of CYTc with metal accumulation and associated modulation of CYTc with reactive oxygen species (ROS) generation in rice seedlings exposed to chromium either hexavalent Cr(VI) or trivalent Cr(III). The result indicates that exposures to both Cr species resulted in significant accumulation of Cr in rice tissues. ROS-dependent growth inhibition of rice seedlings was also evident from both Cr treatments. Changes of CYTc content in roots and shoots maintained almost the same pattern after both Cr exposures. However, dynamically transcriptional levels of rice CYTc genes conducted by real-time quantitative RT-PCR were inconsistent in rice tissues. The results presented here demonstrate that oxidative stresses induced by ROS accumulation do not equally and/or detrimentally influence the perturbations of CYTc content and expression patterns of CYTc genes in rice tissues after Cr exposure, suggesting that the decrease of CYTc levels in roots did not originate ROS accumulation, it may be due to metal-binding properties, while enhancement of CYTc content in shoots was probably a signal of severe growth inhibition owing to ROS accumulation.
细胞色素 c（CYTc）是植物线粒体中负责电子传递的氧化还原活性分子之一。它在金属离子与线粒体蛋白质组的相互作用中很重要，对于深入了解氧化应激过程中的电子传递也很重要。本研究重点阐明了 CYTc 与金属积累的相互作用以及在暴露于六价铬（Cr(VI)）或三价铬（Cr(III)）的水稻幼苗中与活性氧（ROS）生成相关的 CYTc 调节作用。结果表明，两种 Cr 物种的暴露都会导致水稻组织中 Cr 的大量积累。两种 Cr 处理均导致水稻幼苗的 ROS 依赖性生长抑制。在两种 Cr 暴露后，根和茎中 CYTc 含量的变化模式几乎相同。然而，通过实时定量 RT-PCR 进行的水稻 CYTc 基因的动态转录水平在水稻组织中不一致。这里呈现的结果表明，ROS 积累引起的氧化应激不会平等地和/或不利地影响 Cr 暴露后水稻组织中 CYTc 含量和表达模式的干扰，这表明根中 CYTc 水平的降低不是由于 ROS 积累，它可能是由于金属结合特性所致，而茎中 CYTc 含量的增加可能是由于 ROS 积累导致严重生长抑制的信号。
