State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China.
State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Trends Plant Sci. 2020 May;25(5):446-454. doi: 10.1016/j.tplants.2020.01.010. Epub 2020 Mar 3.
In photosynthetic cells, chloroplasts and mitochondria are the sites of the core redox reactions underpinning energy metabolism. Such reactions generate reactive oxygen species (ROS) when oxygen is partially reduced. ROS signaling leads to responses by cells which enable them to adjust to changes in redox status. Recent studies in Arabidopsis thaliana reveal that chloroplast NADH can be used to generate malate which is exported to the mitochondrion where its oxidation regenerates NADH. Oxidation of this NADH produces mitochondrial ROS (mROS) which can activate signaling systems to modulate energy metabolism, and in certain cases can lead to programmed cell death (PCD). We propose the term 'malate circulation' to describe such redistribution of reducing equivalents to mediate energy homeostasis in the cell.
在光合作用的细胞中，叶绿体和线粒体是核心氧化还原反应的发生场所，这些反应是能量代谢的基础。当氧气部分还原时，这类反应会生成活性氧（ROS）。ROS 信号转导会引发细胞做出响应，使细胞能够适应氧化还原状态的变化。最近在拟南芥中的研究揭示，叶绿体中的 NADH 可以用来生成苹果酸，然后苹果酸被运出线粒体并在那里被氧化，从而再生 NADH。这种 NADH 的氧化会产生线粒体 ROS（mROS），它可以激活信号系统来调节能量代谢，在某些情况下，还会导致程序性细胞死亡（PCD）。我们提出“苹果酸循环”这一术语来描述这种还原当量的再分配，以调节细胞内的能量稳态。
