title: Mitochondrial Defects Confer Tolerance against Cellulose Deficiency.
abstract: Because the plant cell wall provides the first line of defense against biotic and abiotic assaults, its functional integrity needs to be maintained under stress conditions. Through a phenotype-based compound screening approach, we identified a novel cellulose synthase inhibitor, designated C17. C17 administration depletes cellulose synthase complexes from the plasma membrane inArabidopsis thaliana, resulting in anisotropic cell elongation and a weak cell wall. Surprisingly, in addition to mutations inCELLULOSE SYNTHASE1(CESA1) andCESA3, a forward genetic screen identified two independent defective genes encoding pentatricopeptide repeat (PPR)-like proteins (CELL WALL MAINTAINER1[CWM1] andCWM2) as conferring tolerance to C17. Functional analysis revealed that mutations in these PPR proteins resulted in defective cytochrome c maturation and activation of mitochondrial retrograde signaling, as evidenced by the induction of an alternative oxidase. These mitochondrial perturbations increased tolerance to cell wall damage induced by cellulose deficiency. Likewise, administration of antimycin A, an inhibitor of mitochondrial complex III, resulted in tolerance toward C17. The C17 tolerance ofcwm2was partially lost upon depletion of the mitochondrial retrograde regulator ANAC017, demonstrating that ANAC017 links mitochondrial dysfunction with the cell wall. In view of mitochondria being a major target of a variety of stresses, our data indicate that plant cells might modulate mitochondrial activity to maintain a functional cell wall when subjected to stresses.
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.|College of Life Sciences, Nanjing Agricultural University, 210095 Nanjing, People's Republic of China.
authors.forename: Zhubing
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.
authors.forename: Rudy
authors.initials: R
authors.lastname: Vanderhaeghen
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.
authors.forename: Toon
authors.identifier: http://orcid.org/0000-0002-1258-5531
authors.initials: T
authors.lastname: Cools
authors.affiliation: Department of Botany, ARC Centre of Excellence in Plant Energy Biology, School of Life Science, La Trobe University, Bundoora 3086, Victoria, Australia.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.
authors.forename: Inge
authors.identifier: http://orcid.org/0000-0001-8125-1239
authors.initials: I
authors.lastname: De Clercq
authors.affiliation: Department of Biology, Ghent University, B-9000 Gent, Belgium.
authors.forename: Olivier
authors.initials: O
authors.lastname: Leroux
authors.affiliation: Compound Screening Facility, VIB, B-9052 Gent, Belgium.
authors.forename: Long
authors.initials: L
authors.lastname: Nguyen
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley 6009, Australia.
authors.forename: Katharina
authors.initials: K
authors.lastname: Belt
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley 6009, Australia.
authors.forename: A Harvey
authors.initials: AH
authors.lastname: Millar
authors.affiliation: Compound Screening Facility, VIB, B-9052 Gent, Belgium.
authors.forename: Dominique
authors.initials: D
authors.lastname: Audenaert
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.|Institut Jean-Pierre Bourgin, INRA, Centre National pour la Recherche Scientifique, AgroParisTech, Université Paris-Saclay, 78026 Versailles Cedex, France.
authors.forename: Pierre
authors.identifier: http://orcid.org/0000-0003-4617-1908
authors.initials: P
authors.lastname: Hilson
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley 6009, Australia.
authors.forename: Ian
authors.identifier: http://orcid.org/0000-0001-5300-1216
authors.initials: I
authors.lastname: Small
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, Centre National pour la Recherche Scientifique, AgroParisTech, Université Paris-Saclay, 78026 Versailles Cedex, France.
authors.forename: Grégory
authors.initials: G
authors.lastname: Mouille
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, Centre National pour la Recherche Scientifique, AgroParisTech, Université Paris-Saclay, 78026 Versailles Cedex, France.
authors.forename: Samantha
authors.initials: S
authors.lastname: Vernhettes
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.
authors.forename: Frank
authors.identifier: http://orcid.org/0000-0002-3147-0860
authors.initials: F
authors.lastname: Van Breusegem
authors.affiliation: Department of Botany, ARC Centre of Excellence in Plant Energy Biology, School of Life Science, La Trobe University, Bundoora 3086, Victoria, Australia.
authors.forename: James
authors.identifier: http://orcid.org/0000-0001-5754-025X
authors.initials: J
authors.lastname: Whelan
authors.affiliation: Institut Jean-Pierre Bourgin, INRA, Centre National pour la Recherche Scientifique, AgroParisTech, Université Paris-Saclay, 78026 Versailles Cedex, France.
authors.forename: Herman
authors.initials: H
authors.lastname: Höfte
authors.affiliation: Department of Plant Systems Biology, VIB, B-9052 Gent, Belgium lieven.deveylder@psb.vib-ugent.be.|Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium.
authors.forename: Lieven
authors.identifier: http://orcid.org/0000-0003-1150-4426
authors.initials: L
authors.lastname: De Veylder