Collins, N.Thordal-Christensen, H.Lipka, V.Bau, S.Kombrink, E.Qiu, J.Huckelhoven, R.Stein, M.Freialdenhoven, A.Somerville, S.Schulze-Lefert, P.2007-07-052007-07-052003Nature, 2003; 425(6961):973-9770028-08361476-4687http://hdl.handle.net/2440/34195Failure of pathogenic fungi to breach the plant cell wall constitutes a major component of immunity of non-host plant species—species outside the pathogen host range—and accounts for a proportion of aborted infection attempts on 'susceptible' host plants (basal resistance).Neither form of penetration resistance is understood at the molecular level. We developed a screen for penetration (pen) mutants of Arabidopsis, which are disabled in non-host penetration resistance against barley powdery mildew, Blumeria graminis f. sp. hordei, and we isolated the PEN1 gene. We also isolated barley ROR2 , which is required for basal penetration resistance against B. g. hordei. The genes encode functionally homologous syntaxins, demonstrating a mechanistic link between non-host resistance and basal penetration resistance in monocotyledons and dicotyledons. We show that resistance in barley requires a SNAP-25 (synaptosome-associated protein, molecular mass 25 kDa) homologue capable of forming a binary SNAP receptor (SNARE) complex with ROR2. Genetic control of vesicle behaviour at penetration sites, and plasma membrane location of PEN1/ROR2, is consistent with a proposed involvement of SNARE-complex-mediated exocytosis and/or homotypic vesicle fusion events in resistance. Functions associated with SNARE-dependent penetration resistance are dispensable for immunity mediated by race-specific resistance (R) genes, highlighting fundamental differences between these two resistance forms.enCell WallFungiArabidopsisHordeumMembrane ProteinsVesicular Transport ProteinsNerve Tissue ProteinsArabidopsis ProteinsCloning, MolecularTwo-Hybrid System TechniquesPlant DiseasesProtein BindingMutationMolecular Sequence DataSNARE ProteinsQa-SNARE ProteinsSynaptosomal-Associated Protein 25Journal articleRQF000002510.1038/nature020760001862306000442-s2.0-024266791713963Collins, N. [0000-0002-5447-6755]