Department of Food and Nutritional Science, College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan.
Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan.
J Exp Bot. 2024 May 3;75(9):2700-2715. doi: 10.1093/jxb/erae061.
Ascorbate peroxidase (APX) reduces H2O2 to H2O by utilizing ascorbate as a specific electron donor and constitutes the ascorbate-glutathione cycle in organelles of plants including chloroplasts, cytosol, mitochondria, and peroxisomes. It has been almost 40 years since APX was discovered as an important plant-specific H2O2-scavenging enzyme, during which time many research groups have conducted molecular physiological analyses. It is now clear that APX isoforms function not only just as antioxidant enzymes but also as important factors in intracellular redox regulation through the metabolism of reactive oxygen species. The function of APX isoforms is regulated at multiple steps, from the transcriptional level to post-translational modifications of enzymes, thereby allowing them to respond flexibly to ever-changing environmental factors and physiological phenomena such as cell growth and signal transduction. In this review, we summarize the physiological functions and regulation mechanisms of expression of each APX isoform.
抗坏血酸过氧化物酶 (APX) 通过利用抗坏血酸作为特定的电子供体将 H2O2 还原为 H2O，构成了包括叶绿体、细胞质、线粒体和过氧化物酶体在内的植物细胞器中的抗坏血酸-谷胱甘肽循环。自 APX 作为一种重要的植物特异性 H2O2 清除酶被发现以来，已经将近 40 年了，在此期间，许多研究小组进行了分子生理分析。现在很清楚，APX 同工酶不仅作为抗氧化酶，而且还作为通过活性氧代谢的细胞内氧化还原调节的重要因素发挥作用。APX 同工酶的功能在多个步骤中受到调节，从转录水平到酶的翻译后修饰，从而使它们能够灵活地响应不断变化的环境因素和生理现象，如细胞生长和信号转导。在这篇综述中，我们总结了每个 APX 同工酶的生理功能和表达调控机制。
