title: Root-knot nematodes induce pattern-triggered immunity in Arabidopsis thaliana roots.
abstract: Root-knot nematodes (RKNs; Meloidogyne spp.) are plant parasites with a broad host range causing great losses worldwide. To parasitize their hosts, RKNs establish feeding sites in roots known as giant cells. The majority of work studying plant-RKN interactions in susceptible hosts addresses establishment of the giant cells and there is limited information on the early defense responses. Here we characterized early defense or pattern-triggered immunity (PTI) against RKNs in Arabidopsis thaliana. To address PTI, we evaluated known canonical PTI signaling mutants with RKNs and investigated the expression of PTI marker genes after RKN infection using both quantitative PCR and β-glucuronidase reporter transgenic lines. We showed that PTI-compromised plants have enhanced susceptibility to RKNs, including the bak1-5 mutant. BAK1 is a common partner of distinct receptors of microbe- and damage-associated molecular patterns. Furthermore, our data indicated that nematode recognition leading to PTI responses involves camalexin and glucosinolate biosynthesis. While the RKN-induced glucosinolate biosynthetic pathway was BAK1-dependent, the camalexin biosynthetic pathway was only partially dependent on BAK1. Combined, our results indicate the presence of BAK1-dependent and -independent PTI against RKNs in A. thaliana, suggesting the existence of diverse nematode recognition mechanisms.
authors.affiliation: Department of Nematology, University of California, Riverside, CA, 92521, USA.
authors.forename: Marcella A
authors.initials: MA
authors.lastname: Teixeira
authors.affiliation: Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Wei
authors.affiliation: Department of Nematology, University of California, Riverside, CA, 92521, USA.|Institute of Integrative Genome Biology, University of California, Riverside, CA, USA.
authors.forename: Isgouhi
authors.initials: I
authors.lastname: Kaloshian
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000235:genetics / Q000276:immunology* / Q000469:parasitology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005961:Glucosinolates / Q000378:metabolism; D006790:Host-Parasite Interactions / Q000276:immunology; D007211:Indoles / Q000378:metabolism; D009154:Mutation; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000276:immunology*; D057865:Plant Immunity; D018517:Plant Roots / Q000469:parasitology; D030821:Plants, Genetically Modified; D011494:Protein Kinases / Q000276:immunology / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D013844:Thiazoles / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics; D014431:Tylenchoidea / Q000472:pathogenicity* / Q000502:physiology; D000094162:Phytoalexins
chemical_list: D029681:Arabidopsis Proteins; D005961:Glucosinolates; D007211:Indoles; D000069452:Pathogen-Associated Molecular Pattern Molecules; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D013844:Thiazoles; D014157:Transcription Factors; C099515:Atmyb5 protein, Arabidopsis; C517320:WRKY11 protein, Arabidopsis; C102405:camalexin; D000094162:Phytoalexins; C586088:LecRK-I.9 protein, Arabidopsis; C463660:BAK1 protein, Arabidopsis; C411853:FLS2 protein, Arabidopsis
keywords: Arabidopsis thaliana; BAK1; Meloidogyne incognita; WRKY11; camalexin; glucosinolate; pattern-triggered immunity; root-knot nematodes (RKNs)