title: S-nitrosylation positively regulates ascorbate peroxidase activity during plant stress responses.
abstract: Nitric oxide (NO) and reactive oxygen species (ROS) are two classes of key signaling molecules involved in various developmental processes and stress responses in plants. The burst of NO and ROS triggered by various stimuli activates downstream signaling pathways to cope with abiotic and biotic stresses. Emerging evidence suggests that the interplay of NO and ROS plays a critical role in regulating stress responses. However, the underpinning molecular mechanism remains poorly understood. Here, we show that NO positively regulates the activity of the Arabidopsis (Arabidopsis thaliana) cytosolic ascorbate peroxidase1 (APX1). We found that S-nitrosylation of APX1 at cysteine (Cys)-32 enhances its enzymatic activity of scavenging hydrogen peroxide, leading to the increased resistance to oxidative stress, whereas a substitution mutation at Cys-32 causes the reduction of ascorbate peroxidase activity and abolishes its responsiveness to the NO-enhanced enzymatic activity. Moreover, S-nitrosylation of APX1 at Cys-32 also plays an important role in regulating immune responses. These findings illustrate a unique mechanism by which NO regulates hydrogen peroxide homeostasis in plants, thereby establishing a molecular link between NO and ROS signaling pathways.
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Huanjie
authors: H
authors: Yang
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Jinye
authors: J
authors: Mu
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Lichao
authors: L
authors: Chen
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Jian
authors: J
authors: Feng
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Jiliang
authors: J
authors: Hu
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Lei
authors: L
authors: Li
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.).
authors: Jian-Min
authors: JM
authors: Zhou
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (H.Y., J.M., L.C., J.F., J.H., L.L., J.-M.Z., J.Z.); andThe University of Chinese Academy of Sciences, Beijing 100049, China (H.Y., L.C., L.L.) jrzuo@genetics.ac.cn.
authors: Jianru
authors: J
authors: Zuo
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060387:Ascorbate Peroxidases / Q000235:genetics / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism; D008027:Light; D009569:Nitric Oxide / Q000378:metabolism*; D018384:Oxidative Stress; D030821:Plants, Genetically Modified; D017382:Reactive Oxygen Species / Q000378:metabolism*; D036226:Seedlings / Q000201:enzymology / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; D017382:Reactive Oxygen Species; D009569:Nitric Oxide; D006861:Hydrogen Peroxide; C555290:APX1 protein, Arabidopsis; D060387:Ascorbate Peroxidases