title: SHORT-ROOT Deficiency Alleviates the Cell Death Phenotype of the Arabidopsis catalase2 Mutant under Photorespiration-Promoting Conditions.
abstract: Hydrogen peroxide (H2O2) can act as a signaling molecule that influences various aspects of plant growth and development, including stress signaling and cell death. To analyze molecular mechanisms that regulate the response to increased H2O2 levels in plant cells, we focused on the photorespiration-dependent peroxisomal H2O2 production in Arabidopsis thaliana mutants lacking CATALASE2 (CAT2) activity (cat2-2). By screening for second-site mutations that attenuate the PSII maximum efficiency (Fv'/Fm') decrease and lesion formation linked to the cat2-2 phenotype, we discovered that a mutation in SHORT-ROOT (SHR) rescued the cell death phenotype of cat2-2 plants under photorespiration-promoting conditions. SHR deficiency attenuated H2O2-dependent gene expression, oxidation of the glutathione pool, and ascorbate depletion in a cat2-2 genetic background upon exposure to photorespiratory stress. Decreased glycolate oxidase and catalase activities together with accumulation of glycolate further implied that SHR deficiency impacts the cellular redox homeostasis by limiting peroxisomal H2O2 production. The photorespiratory phenotype of cat2-2 mutants did not depend on the SHR functional interactor SCARECROW and the sugar signaling component ABSCISIC ACID INSENSITIVE4, despite the requirement for exogenous sucrose for cell death attenuation in cat2-2 shr-6 double mutants. Our findings reveal a link between SHR and photorespiratory H2O2 production that has implications for the integration of developmental and stress responses.
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium Structural Biology Research Center, VIB, 1050 Brussels, Belgium Structural Biology Brussels Laboratory, Vrije Universiteit Brussel, 1050 Brussels, Belgium Brussels Center for Redox Biology, 1050 Brussels, Belgium Division of Plant Biology, Department of Biosciences, Viikki Plant Science Center, University of Helsinki, FI-00014 Helsinki, Finland.
authors.forename: Cezary
authors.initials: C
authors.lastname: Waszczak
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Pavel I
authors.identifier: 0000-0003-2737-0493
authors.initials: PI
authors.lastname: Kerchev
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Per
authors.identifier: 0000-0003-3097-8387
authors.initials: P
authors.lastname: Mühlenbock
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Frank A
authors.initials: FA
authors.lastname: Hoeberichts
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: Van Der Kelen
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France.
authors.forename: Amna
authors.identifier: 0000-0001-9959-1362
authors.initials: A
authors.lastname: Mhamdi
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Patrick
authors.identifier: 0000-0003-4667-2294
authors.initials: P
authors.lastname: Willems
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Jordi
authors.initials: J
authors.lastname: Denecker
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Kumpf
authors.affiliation: Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, 91405 Orsay, France.
authors.forename: Graham
authors.identifier: 0000-0003-1980-4554
authors.initials: G
authors.lastname: Noctor
authors.affiliation: Structural Biology Research Center, VIB, 1050 Brussels, Belgium Structural Biology Brussels Laboratory, Vrije Universiteit Brussel, 1050 Brussels, Belgium Brussels Center for Redox Biology, 1050 Brussels, Belgium.
authors.forename: Joris
authors.identifier: 0000-0002-2128-8264
authors.initials: J
authors.lastname: Messens
authors.affiliation: Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium frank.vanbreusegem@psb.vib-ugent.be.
authors.forename: Frank
authors.identifier: 0000-0002-3147-0860
authors.initials: F
authors.lastname: Van Breusegem
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002374:Catalase / Q000235:genetics / Q000378:metabolism*; D016923:Cell Death / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D006861:Hydrogen Peroxide / Q000378:metabolism; D010084:Oxidation-Reduction; D030821:Plants, Genetically Modified / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C410510:SHORT ROOT protein, Arabidopsis; D014157:Transcription Factors; D006861:Hydrogen Peroxide; D002374:Catalase