title: A new proteinaceous pathogen-associated molecular pattern (PAMP) identified in Ascomycete fungi induces cell death in Solanaceae.
abstract: Pathogen-associated molecular patterns (PAMPs) are detected by plant pattern recognition receptors (PRRs), which gives rise to PAMP-triggered immunity (PTI). We characterized a novel fungal PAMP, Cell Death Inducing 1 (RcCDI1), identified in the Rhynchosporium commune transcriptome sampled at an early stage of barley (Hordeum vulgare) infection. The ability of RcCDI1 and its homologues from different fungal species to induce cell death in Nicotiana benthamiana was tested following agroinfiltration or infiltration of recombinant proteins produced by Pichia pastoris. Virus-induced gene silencing (VIGS) and transient expression of Phytophthora infestans effectors PiAVR3a and PexRD2 were used to assess the involvement of known components of PTI in N. benthamiana responses to RcCDI1. RcCDI1 was highly upregulated early during barley colonization with R. commune. RcCDI1 and its homologues from different fungal species, including Zymoseptoria tritici, Magnaporthe oryzae and Neurospora crassa, exhibited PAMP activity, inducing cell death in Solanaceae but not in other families of dicots or monocots. RcCDI1-triggered cell death was shown to require N. benthamiana Brassinosteroid insensitive 1-Associated Kinase 1 (NbBAK1), N. benthamiana suppressor of BIR1-1 (NbSOBIR1) and N. benthamiana SGT1 (NbSGT1), but was not suppressed by PiAVR3a or PexRD2. We report the identification of a novel Ascomycete PAMP, RcCDI1, recognized by Solanaceae but not by monocots, which activates cell death through a pathway that is distinct from that triggered by the oomycete PAMP INF1.
authors.affiliation: Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Barbara
authors.initials: B
authors.lastname: Franco-Orozco
authors.affiliation: Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Adokiye
authors.initials: A
authors.lastname: Berepiki
authors.affiliation: Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, UK.
authors.forename: Olaya
authors.initials: O
authors.lastname: Ruiz
authors.affiliation: Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Louise
authors.initials: L
authors.lastname: Gamble
authors.affiliation: Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Lucie L
authors.initials: LL
authors.lastname: Griffe
authors.affiliation: Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Shumei
authors.initials: S
authors.lastname: Wang
authors.affiliation: Division of Plant Sciences, University of Dundee (at JHI), Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Paul R J
authors.initials: PRJ
authors.lastname: Birch
authors.affiliation: Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, UK.
authors.forename: Kostya
authors.identifier: http://orcid.org/0000-0001-6324-4123
authors.initials: K
authors.lastname: Kanyuka
authors.affiliation: Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Avrova
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D016923:Cell Death; D017124:Conserved Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D001467:Hordeum / Q000382:microbiology; D054884:Host-Pathogen Interactions / Q000502:physiology*; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000378:metabolism*; D010802:Phylogeny; D059828:Plant Cells / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D019657:Solanaceae / Q000166:cytology / Q000382:microbiology*; D014026:Nicotiana / Q000235:genetics / Q000382:microbiology; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: C562170:AVR3a protein, Phytophthora infestans; D005656:Fungal Proteins; D000069452:Pathogen-Associated Molecular Pattern Molecules; D010940:Plant Proteins; D037521:Virulence Factors
keywords: 
  Rhynchosporium commune
  ; Ascomycete; Solanaceae; cell death; elicitor; fungal; pathogen; pathogen-associated molecular pattern (PAMP)