title: Stress-induced GSK3 regulates the redox stress response by phosphorylating glucose-6-phosphate dehydrogenase in Arabidopsis.
abstract: Diverse stresses such as high salt conditions cause an increase in reactive oxygen species (ROS), necessitating a redox stress response. However, little is known about the signaling pathways that regulate the antioxidant system to counteract oxidative stress. Here, we show that a Glycogen Synthase Kinase3 from Arabidopsis thaliana (ASKα) regulates stress tolerance by activating Glc-6-phosphate dehydrogenase (G6PD), which is essential for maintaining the cellular redox balance. Loss of stress-activated ASKα leads to reduced G6PD activity, elevated levels of ROS, and enhanced sensitivity to salt stress. Conversely, plants overexpressing ASKα have increased G6PD activity and low levels of ROS in response to stress and are more tolerant to salt stress. ASKα stimulates the activity of a specific cytosolic G6PD isoform by phosphorylating the evolutionarily conserved Thr-467, which is implicated in cosubstrate binding. Our results reveal a novel mechanism of G6PD adaptive regulation that is critical for the cellular stress response.
authors.affiliation: Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, 1030 Viena, Austria.
authors.forename: Silvia
authors.initials: S
authors.lastname: Dal Santo
authors.forename: Hansjörg
authors.initials: H
authors.lastname: Stampfl
authors.forename: Julia
authors.initials: J
authors.lastname: Krasensky
authors.forename: Stefan
authors.initials: S
authors.lastname: Kempa
authors.forename: Yves
authors.initials: Y
authors.lastname: Gibon
authors.forename: Elena
authors.initials: E
authors.lastname: Petutschnig
authors.forename: Wilfried
authors.initials: W
authors.lastname: Rozhon
authors.forename: Alexander
authors.initials: A
authors.lastname: Heuck
authors.forename: Tim
authors.initials: T
authors.lastname: Clausen
authors.forename: Claudia
authors.initials: C
authors.lastname: Jonak
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media / Q000378:metabolism; D004789:Enzyme Activation; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D018525:Germination; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D038362:Glycogen Synthase Kinase 3 / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010766:Phosphorylation; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D055051:Salt-Tolerant Plants / Q000201:enzymology / Q000235:genetics; D015398:Signal Transduction; D012965:Sodium Chloride; D013912:Threonine / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D003470:Culture Media; D007527:Isoenzymes; D017382:Reactive Oxygen Species; D013912:Threonine; D012965:Sodium Chloride; D005954:Glucosephosphate Dehydrogenase; C085936:ATSK11 protein, Arabidopsis; D038362:Glycogen Synthase Kinase 3