title: Resistance of Arabidopsis thaliana to the green peach aphid, Myzus persicae, involves camalexin and is regulated by microRNAs.
abstract: · Small RNAs play important roles in resistance to plant viruses and the complex responses against pathogens and leaf-chewing insects. · We investigated whether small RNA pathways are involved in Arabidopsis resistance against a phloem-feeding insect, the green peach aphid (Myzus persicae). We used a 2-wk fecundity assay to assess aphid performance on Arabidopsis RNA silencing and defence pathway mutants. Quantitative real-time polymerase chain reaction was used to monitor the transcriptional activity of defence-related genes in plants of varying aphid susceptibility. High-performance liquid chromatography-mass spectrometry was employed to measure the accumulation of the antimicrobial compound camalexin. Artificial diet assays allowed the assessment of the effect of camalexin on aphid performance. · Myzus persicae produces significantly less progeny on Arabidopsis microRNA (miRNA) pathway mutants. Plants unable to process miRNAs respond to aphid infestation with increased induction of PHYTOALEXIN DEFICIENT3 (PAD3) and production of camalexin. Aphids ingest camalexin when feeding on Arabidopsis and are more successful on pad3 and cyp79b2/cyp79b3 mutants defective in camalexin production. Aphids produce less progeny on artificial diets containing camalexin. · Our data indicate that camalexin functions beyond antimicrobial defence to also include hemipteran insects. This work also highlights the extensive role of the miRNA-mediated regulation of secondary metabolic defence pathways with relevance to resistance against a hemipteran pest.
authors.affiliation: Department of Cell and Developmental Biology, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK.
authors.forename: Graeme J
authors.initials: GJ
authors.lastname: Kettles
authors.affiliation: Department of Cell and Developmental Biology, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK.
authors.forename: Claire
authors.initials: C
authors.lastname: Drurey
authors.affiliation: Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK.
authors.forename: Henk-Jan
authors.initials: HJ
authors.lastname: Schoonbeek
authors.affiliation: Department of Cell and Developmental Biology, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK.
authors.forename: Andy J
authors.initials: AJ
authors.lastname: Maule
authors.affiliation: Department of Cell and Developmental Biology, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK.
authors.forename: Saskia A
authors.initials: SA
authors.lastname: Hogenhout
mesh_terms: D000818:Animals; D001042:Aphids / Q000187:drug effects / Q000502:physiology*; D017360:Arabidopsis / Q000033:anatomy & histology / Q000235:genetics* / Q000276:immunology / Q000469:parasitology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics*; D005030:Ethylenes / Q000378:metabolism; D005247:Feeding Behavior / Q000187:drug effects; D005298:Fertility / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007211:Indoles / Q000378:metabolism* / Q000494:pharmacology; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D054883:Oxylipins / Q000378:metabolism; D052585:Phloem / Q000187:drug effects / Q000378:metabolism / Q000469:parasitology; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology; D027861:Prunus / Q000469:parasitology*; D012098:Reproduction / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D016019:Survival Analysis; D013844:Thiazoles / Q000378:metabolism* / Q000494:pharmacology; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D000094162:Phytoalexins
chemical_list: D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D005030:Ethylenes; D007211:Indoles; D035683:MicroRNAs; D054883:Oxylipins; D013844:Thiazoles; C102405:camalexin; D000094162:Phytoalexins; C011006:jasmonic acid; C036216:ethylene