title: Pathogen and Circadian Controlled 1 (PCC1) regulates polar lipid content, ABA-related responses, and pathogen defence in Arabidopsis thaliana.
abstract: Pathogen and Circadian Controlled 1 (PCC1) was previously characterized as a regulator of defence against pathogens and stress-activated transition to flowering. Plants expressing an RNA interference construct for the PCC1 gene (iPCC1 plants) showed a pleiotropic phenotype. They were hypersensitive to abscisic acid (ABA) as shown by reduced germination potential and seedling establishment, as well as reduced stomatal aperture and main root length in ABA-supplemented media. In addition, iPCC1 plants displayed alterations in polar lipid contents and their corresponding fatty acids. Importantly, a significant reduction in the content of phosphatidylinositol (PI) was observed in iPCC1 leaves when compared with wild-type plants. A trend in reduced levels of 18:0 and increased levels of 18:2 and particularly 18:3 was also detected in several classes of polar lipids. The enhanced ABA-mediated responses and the reduced content of PI might be responsible for iPCC1 plants displaying a complex pattern of defence against pathogens of different lifestyles. iPCC1 plants were more susceptible to the hemi-biotrophic oomycete pathogen Phytophthora brassicae and more resistant to the necrotrophic fungal pathogen Botrytis cinerea compared with wild-type plants.
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas (CSIC-Universidad Politécnica de Valencia), Ciudad Politécnica de la Innovación, Edificio 8E, Avda. Ingeniero Fausto Elio s/n, 46022 Valencia, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Mir
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Hernández
authors.forename: Eliane
authors.initials: E
authors.lastname: Abou-Mansour
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Martínez-Rivas
authors.forename: Félix
authors.initials: F
authors.lastname: Mauch
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Métraux
authors.forename: José
authors.initials: J
authors.lastname: León
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060467:Disease Resistance / Q000187:drug effects / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D010716:Phosphatidylinositols / Q000378:metabolism; D010935:Plant Diseases
chemical_list: D029681:Arabidopsis Proteins; C484238:PCC1 protein, Arabidopsis; D010716:Phosphatidylinositols; D000040:Abscisic Acid
keywords: ABA; Arabidopsis; defence; lipids; transcriptome.