title: Plasmodesmata-located protein overexpression negatively impacts the manifestation of systemic acquired resistance and the long-distance movement of Defective in Induced Resistance1 in Arabidopsis.
abstract: Systemic acquired resistance (SAR) is a plant defence response that provides immunity to distant uninfected leaves after an initial localised infection. The lipid transfer protein (LTP) Defective in Induced Resistance1 (DIR1) is an essential component of SAR that moves from induced to distant leaves following a SAR-inducing local infection. To understand how DIR1 is transported to distant leaves during SAR, we analysed DIR1 movement in transgenic Arabidopsis lines with reduced cell-to-cell movement caused by the overexpression of Plasmodesmata-Located Proteins PDLP1 and PDLP5. These PDLP-overexpressing lines were defective for SAR, and DIR1 antibody signals were not observed in phloem sap-enriched petiole exudates collected from distant leaves. Our data support the idea that cell-to-cell movement of DIR1 through plasmodesmata is important during long-distance SAR signalling in Arabidopsis.
authors.affiliation: Department of Biology, McMaster University, Hamilton, ON, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Carella
authors.forename: M
authors.initials: M
authors.lastname: Isaacs
authors.forename: R K
authors.initials: RK
authors.lastname: Cameron
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D060467:Disease Resistance; D050556:Fatty Acid-Binding Proteins; D018506:Gene Expression Regulation, Plant; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D030821:Plants, Genetically Modified; D031425:Plasmodesmata / Q000378:metabolism*; D021381:Protein Transport
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D050556:Fatty Acid-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C528450:PDLP1a protein, Arabidopsis; C586778:PDLP5 protein, Arabidopsis; C466483:dir1-1 protein, Arabidopsis
keywords: Cell-to-cell movement; DIR1; PDLP; lipid transfer protein; long-distance signalling; plasmodesmata; systemic acquired resistance