title: Assessing redox state and reactive oxygen species in circadian rhythmicity.
abstract: Redox homeostasis is an important parameter of cell function and cell signaling. Spatial and temporal alterations of redox state control metabolism, developmental processes, as well as acute responses to environmental stresses and stress acclimation. Redox homeostasis is also linked to the circadian clock. This chapter introduces methods to assess important redox parameters such as the low molecular weight redox metabolites glutathione and ascorbate, their amount and redox state, and H2O2 as reactive oxygen species. In vivo redox cell imaging is described by use of the reduction-oxidation sensitive green fluorescent protein (roGFP). Finally, on the level of posttranslational redox modifications of proteins, methods are shown to assess hyperoxidation of 2-cysteine peroxiredoxin and glutathionylation of peroxiredoxin IIE. The redox state of 2-cysteine peroxiredoxin has been identified as a transcription-independent marker of circadian rhythmicity.
authors.affiliation: Biochemistry and Physiology of Plants, Faculty of Biology, Bielefeld University, 100131, Bielefeld, 33615, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: König
authors.forename: Helena
authors.initials: H
authors.lastname: Galliardt
authors.forename: Marten
authors.initials: M
authors.lastname: Moore
authors.forename: Patrick
authors.initials: P
authors.lastname: Treffon
authors.forename: Thorsten
authors.initials: T
authors.lastname: Seidel
authors.forename: Karl-Josef
authors.initials: KJ
authors.lastname: Dietz
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology*; D003545:Cysteine / Q000378:metabolism; D015870:Gene Expression; D017930:Genes, Reporter; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D005978:Glutathione; D003545:Cysteine