title: Redox-sensitive YFP sensors for monitoring dynamic compartment-specific glutathione redox state.
abstract: Intracellular redox homeostasis is crucial for many cellular functions but accurate measurements of cellular compartment-specific redox states remain technically challenging. Genetically encoded biosensors including the glutathione-specific redox-sensitive yellow fluorescent protein (rxYFP) may provide an alternative way to overcome the limitations of conventional glutathione/glutathione disulfide (GSH/GSSG) redox measurements. This study describes the use of rxYFP sensors for investigating compartment-specific steady redox state and their dynamics in response to stress in human cells. RxYFP expressed in the cytosol, nucleus, or mitochondrial matrix of HeLa cells was responsive to the intracellular redox state changes induced by reducing as well as oxidizing agents. Compartment-targeted rxYFP sensors were able to detect different steady-state redox conditions among the cytosol, nucleus, and mitochondrial matrix. These sensors expressed in human epidermal keratinocytes HEK001 responded to stress induced by ultraviolet A radiation in a dose-dependent manner. Furthermore, rxYFP sensors were able to sense dynamic and compartment-specific redox changes caused by 100 μM hydrogen peroxide (H2O2). Mitochondrial matrix-targeted rxYFP displayed a greater dynamics of oxidation in response to a H2O2 challenge than the cytosol- and nucleus-targeted sensors, largely due to a more alkaline local pH environment. These observations support the view that mitochondrial glutathione redox state is maintained and regulated independently from that of the cytosol and nucleus. Taken together, our data show the robustness of the rxYFP sensors to measure compartmental redox changes in human cells. Complementary to existing redox sensors and conventional redox measurements, compartment-targeted rxYFP sensors provide a novel tool for examining mammalian cell redox homeostasis, permitting high-resolution readout of steady glutathione state and dynamics of redox changes.
authors.affiliation: Centre National de la Recherche Scientifique, UMR3348, Genotoxic Stress and Cancer, Orsay, 91405, France; Institut Curie, Centre de Recherche, Orsay, 91405, France.
authors.forename: Agata
authors.initials: A
authors.lastname: Banach-Latapy
authors.affiliation: Centre National de la Recherche Scientifique, UMR3348, Genotoxic Stress and Cancer, Orsay, 91405, France; Institut Curie, Centre de Recherche, Orsay, 91405, France.
authors.forename: Tiantian
authors.initials: T
authors.lastname: He
authors.affiliation: Centre National de la Recherche Scientifique, UMR3348, Genotoxic Stress and Cancer, Orsay, 91405, France; Institut Curie, Centre de Recherche, Orsay, 91405, France.
authors.forename: Michèle
authors.initials: M
authors.lastname: Dardalhon
authors.affiliation: Centre National de la Recherche Scientifique, UMR3348, Genotoxic Stress and Cancer, Orsay, 91405, France; Institut Curie, Centre de Recherche, Orsay, 91405, France.
authors.forename: Laurence
authors.initials: L
authors.lastname: Vernis
authors.affiliation: Centre National de la Recherche Scientifique, UMR3348, Genotoxic Stress and Cancer, Orsay, 91405, France; Institut Curie, Centre de Recherche, Orsay, 91405, France.
authors.forename: Roland
authors.initials: R
authors.lastname: Chanet
authors.affiliation: Centre National de la Recherche Scientifique, UMR3348, Genotoxic Stress and Cancer, Orsay, 91405, France; Institut Curie, Centre de Recherche, Orsay, 91405, France. Electronic address: meng-er.huang@curie.fr.
authors.forename: Meng-Er
authors.initials: ME
authors.lastname: Huang
mesh_terms: D001426:Bacterial Proteins; D015374:Biosensing Techniques / Q000379:methods*; D015153:Blotting, Western; D002460:Cell Line; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D008164:Luminescent Proteins; D010084:Oxidation-Reduction; D014162:Transfection
chemical_list: D001426:Bacterial Proteins; D008164:Luminescent Proteins; C054562:yellow fluorescent protein, Bacteria; D005978:Glutathione
keywords: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; BSO; DMEM; DTT; Dulbecco modified Eagle’s medium; ER; FBS; GSH; GSSG; Glutathione; Gpx; Grx; H(2)O(2); L-buthionine-(S,R)-sulfoximine; MLS; MTT; NES; NLS; ROS; Redox; Redox compartmentalization; Redox-sensitive sensor; SDS-PAGE; Trx; UVA; dithiothreitol; endoplasmic reticulum; fetal bovine serum; glutaredoxin; glutathione disulfide; glutathione peroxidase; hydrogen peroxide; mitochondrial leader sequence; nuclear export signal; nuclear localization signal; reactive oxygen species; redox-sensitive yellow fluorescent protein; reduced glutathione; reduction-oxidation green fluorescent protein; roGFP; rxYFP; sodium dodecyl sulfate polyacrylamide gel electrophoresis; thioredoxin; ultraviolet A; γ-GCS; γ-glutamylcysteine synthetase