title: Three Pectin Methylesterase Inhibitors Protect Cell Wall Integrity for Arabidopsis Immunity toBotrytis.
abstract: Infection by necrotrophs is a complex process that starts with the breakdown of the cell wall (CW) matrix initiated by CW-degrading enzymes and results in an extensive tissue maceration. Plants exploit induced defense mechanisms based on biochemical modification of the CW components to protect themselves from enzymatic degradation. The pectin matrix is the main CW target ofBotrytis cinerea, and pectin methylesterification status is strongly altered in response to infection. The methylesterification of pectin is controlled mainly by pectin methylesterases (PMEs), whose activity is posttranscriptionally regulated by endogenous protein inhibitors (PMEIs). Here, AtPMEI10, AtPMEI11, and AtPMEI12 are identified as functional PMEIs induced in Arabidopsis (Arabidopsis thaliana) duringB. cinereainfection. AtPMEI expression is strictly regulated by jasmonic acid and ethylene signaling, while only AtPMEI11 expression is controlled by PME-related damage-associated molecular patterns, such as oligogalacturonides and methanol. The decrease of pectin methylesterification during infection is higher and the immunity toB. cinereais compromised inpmei10,pmei11, andpmei12mutants with respect to the control plants. A higher stimulation of the fungal oxalic acid biosynthetic pathway also can contribute to the higher susceptibility ofpmeimutants. The lack ofPMEIexpression does not affect hemicellulose strengthening, callose deposition, and the synthesis of structural defense proteins, proposed as CW-remodeling mechanisms exploited by Arabidopsis to resist CW degradation uponB. cinereainfection. We show that PME activity and pectin methylesterification are dynamically modulated by PMEIs duringB. cinereainfection. Our findings point to AtPMEI10, AtPMEI11, and AtPMEI12 as mediators of CW integrity maintenance in plant immunity.
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.); vincenzo.lionetti@uniroma1.it.|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and vincenzo.lionetti@uniroma1.it.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.) vincenzo.lionetti@uniroma1.it.
authors.forename: Vincenzo
authors.identifier: 0000-0002-2262-1479
authors.initials: V
authors.lastname: Lionetti
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.).|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.).
authors.forename: Eleonora
authors.initials: E
authors.lastname: Fabri
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.).|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.).
authors.forename: Monica
authors.identifier: 0000-0001-8668-4711
authors.initials: M
authors.lastname: De Caroli
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.).|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.).
authors.forename: Aleksander R
authors.identifier: 0000-0001-7481-8639
authors.initials: AR
authors.lastname: Hansen
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.).|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.).
authors.forename: William G T
authors.initials: WG
authors.lastname: Willats
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.).|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.).
authors.forename: Gabriella
authors.identifier: 0000-0002-3420-8788
authors.initials: G
authors.lastname: Piro
authors.affiliation: Dipartimento di Biologia e Biotecnologie, Charles Darwin, Sapienza Università di Roma, 00185 Rome, Italy (V.L., E.F., D.B.).|Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, 73100 Lecce, Italy (M.D.C., G.P.); and.|Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, 1871 Copenhagen, Denmark (A.R.H., W.G.T.W.).
authors.forename: Daniela
authors.identifier: 0000-0002-1609-6188
authors.initials: D
authors.lastname: Bellincampi
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D020171:Botrytis / Q000502:physiology; D002265:Carboxylic Ester Hydrolases / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D002473:Cell Wall / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D004791:Enzyme Inhibitors / Q000145:classification / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions; D007527:Isoenzymes / Q000145:classification / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D009154:Mutation; D010368:Pectins / Q000378:metabolism; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D057865:Plant Immunity / Q000235:genetics; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D010368:Pectins; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase