title: Evidence for ACD5 ceramide kinase activity involvement in Arabidopsis response to cold stress.
abstract: Although sphingolipids emerged as important signals for plant response to low temperature, investigations have been limited so far to the function of long-chain base intermediates. The formation and function of ceramide phosphates (Cer-Ps) in chilled Arabidopsis were explored. Cer-Ps were analysed by thin layer chromatography (TLC) following in vivo metabolic radiolabelling. Ceramide kinase activity, gene expression and growth phenotype were determined in unstressed and cold-stressed wild type (WT) and Arabidopsis ceramide kinase mutant acd5. A rapid and transient formation of Cer-P occurs in cold-stressed WT Arabidopsis plantlets and cultured cells, which is strongly impaired in acd5 mutant. Although concomitant, Cer-P formation is independent of long-chain base phosphate (LCB-P) formation. No variation of ceramide kinase activity was measured in vitro in WT plantlets upon cold stress but the activity in acd5 mutant was further reduced by cold stress. At the seedling stage, acd5 response to cold was similar to that of WT. Nevertheless, acd5 seed germination was hypersensitive to cold and abscisic acid (ABA), and ABA-dependent gene expression was modified in acd5 seeds when germinated at low temperature. Our data involve for the first time Cer-P and ACD5 in low temperature response and further underline the complexity of sphingolipid signalling operating during cold stress.
authors.affiliation: UFR 927, Sorbonne Universités, UPMC Univ Paris 06, F-75252, Paris, France.
authors.forename: Christelle
authors.initials: C
authors.lastname: Dutilleul
authors.affiliation: UFR 927, Sorbonne Universités, UPMC Univ Paris 06, F-75252, Paris, France.
authors.forename: Heidy
authors.initials: H
authors.lastname: Chavarria
authors.affiliation: UFR 927, Sorbonne Universités, UPMC Univ Paris 06, F-75252, Paris, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Rézé
authors.affiliation: UFR 927, Sorbonne Universités, UPMC Univ Paris 06, F-75252, Paris, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Sotta
authors.affiliation: Institut de Biologie Paris-Seine (IBPS), Sorbonne Universités, F-75252, Paris, France.|Biologie du Développement, Sorbonne Universités, F-75252, Paris, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Baudouin
authors.affiliation: UFR 927, Sorbonne Universités, UPMC Univ Paris 06, F-75252, Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Guillas
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002518:Ceramides / Q000378:metabolism; D003080:Cold Temperature; D018506:Gene Expression Regulation, Plant; D018525:Germination; D009154:Mutation; D010641:Phenotype; D010766:Phosphorylation; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism; D036226:Seedlings / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D012639:Seeds / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; D002518:Ceramides; D010937:Plant Growth Regulators; D000040:Abscisic Acid; D017853:Phosphotransferases (Alcohol Group Acceptor); C000598951:ACD5 protein, Arabidopsis
keywords: ABA; ACCELERATED CELL DEATH5; Arabidopsis thaliana; ceramide phosphate; chilling