title: The importance of cardiolipin synthase for mitochondrial ultrastructure, respiratory function, plant development, and stress responses in Arabidopsis.
abstract: Cardiolipin (CL) is the signature phospholipid of the mitochondrial inner membrane. In animals and yeast (Saccharomyces cerevisiae), CL depletion affects the stability of respiratory supercomplexes and is thus crucial to the energy metabolism of obligate aerobes. In eukaryotes, the last step of CL synthesis is catalyzed by CARDIOLIPIN SYNTHASE (CLS), encoded by a single-copy gene. Here, we characterize a cls mutant in Arabidopsis thaliana, which is devoid of CL. In contrast to yeast cls, where development is little affected, Arabidopsis cls seedlings are slow developing under short-day conditions in vitro and die if they are transferred to long-day (LD) conditions. However, when transferred to soil under LD conditions under low light, cls plants can reach the flowering stage, but they are not fertile. The cls mitochondria display abnormal ultrastructure and reduced content of respiratory complex I/complex III supercomplexes. The marked accumulation of tricarboxylic acid cycle derivatives and amino acids demonstrates mitochondrial dysfunction. Mitochondrial and chloroplastic antioxidant transcripts are overexpressed in cls leaves, and cls protoplasts are more sensitive to programmed cell death effectors, UV light, and heat shock. Our results show that CLS is crucial for correct mitochondrial function and development in Arabidopsis under both optimal and stress conditions.
authors.affiliation: Institut de Biologie des Plantes, Saclay Plant Science, Université de Paris-Sud XI, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8618, 91405 Orsay cedex, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Pineau
authors.forename: Mickaël
authors.initials: M
authors.lastname: Bourge
authors.forename: Jessica
authors.initials: J
authors.lastname: Marion
authors.forename: Caroline
authors.initials: C
authors.lastname: Mauve
authors.forename: Francoise
authors.initials: F
authors.lastname: Gilard
authors.forename: Lilly
authors.initials: L
authors.lastname: Maneta-Peyret
authors.forename: Patrick
authors.initials: P
authors.lastname: Moreau
authors.forename: Béatrice
authors.initials: B
authors.lastname: Satiat-Jeunemaître
authors.forename: Spencer C
authors.initials: SC
authors.lastname: Brown
authors.forename: Rosine
authors.initials: R
authors.lastname: De Paepe
authors.forename: Antoine
authors.initials: A
authors.lastname: Danon
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology*; D002308:Cardiolipins / Q000737:chemistry; D004269:DNA, Bacterial; D008027:Light; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D008928:Mitochondria / Q000648:ultrastructure*; D051336:Mitochondrial Membranes / Q000737:chemistry; D016254:Mutagenesis, Insertional; D011523:Protoplasts / Q000201:enzymology; D036226:Seedlings / Q000254:growth & development; D013312:Stress, Physiological; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics / Q000502:physiology*
chemical_list: D000975:Antioxidants; D029681:Arabidopsis Proteins; D002308:Cardiolipins; D004269:DNA, Bacterial; D008565:Membrane Proteins; C036483:T-DNA; D017855:Transferases (Other Substituted Phosphate Groups); C100091:cardiolipin synthetase