Reactive oxygen/nitrogen species and antioxidant defenses in Lotus japonicus

17 Pags.- 1 Tabl.- 1 Fig. The definitive version is available at: http://link.springer.com/book/10.1007/978-3-662-44270-8Reactive oxygen/nitrogen species (ROS/RNS) are potentially cytotoxic molecules because they can generate oxidative/nitrosative stress. However, ROS and RNS, at concentrations tightly regulated by antioxidants, also serve useful purposes in processes such as organ development, abiotic and biotic stress response, and redox signaling. Antioxidant enzymes and metabolites are abundant in plants and particularly in legume nodules. Most of the enzymes involved in antioxidant defense are encoded by multigene families and occur as multiple isoforms in various cellular compartments, forming a dynamic network that is spatiotemporally regulated. Genomic, transcriptomic, and proteomic analyses of model legumes, such as Lotus japonicus and Medicago truncatula, are unveiling a complex regulation of antioxidant pathways in different tissues and especially during the symbiotic interaction with rhizobia. This regulation includes alternatively spliced forms of the genes and post-translational modifications of the proteins, which with no doubt will be the subject of intense research over the next years.Rcsearch of our lahoratoty was funded by the Ministry of Economy and Competitivity (grants AGL2008-0l298 and AGL2011-24524, cofunded by Fondo Europeo de Desarrollo Regional) and by Gobierno de Aragón (group A53).Peer reviewe