title: Proteomic analysis reveals an aflatoxin-triggered immune response in cotyledons of Arachis hypogaea infected with Aspergillus flavus.
abstract: An immune response is triggered in host cells when host receptors recognize conserved molecular motifs, pathogen-associated molecular patterns (PAMPs), such as β-glucans, and chitin at the cell surface of a pathogen. Effector-triggered immunity occurs when pathogens deliver effectors into the host cell to suppress the first immune signaling. Using a differential proteomic approach, we identified an array of proteins responding to aflatoxins in cotyledons of peanut (Arachis hypogaea) infected with aflatoxin-producing (toxigenic) but not nonaflatoxin-producing (atoxigenic) strains of Aspergillus flavus. These proteins are involved in immune signaling and PAMP perception, DNA and RNA stabilization, induction of defense, innate immunity, hypersensitive response, biosynthesis of phytoalexins, cell wall responses, peptidoglycan assembly, penetration resistance, condensed tannin synthesis, detoxification, and metabolic regulation. Gene expression analysis confirmed the differential abundance of proteins in peanut cotyledons supplemented with aflatoxins, with or without infection with the atoxigenic strain. Similarly, peanut germination and A. flavus growth were altered in response to aflatoxin B1. These findings show an additional immunity initiated by aflatoxins. With the PAMP- and effector-triggered immune responses, this immunity constitutes the third immune response of the immune system in peanut cotyledon cells. The system is also a three-grade coevolution of plant-pathogen interaction.
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Zizhang
authors.initials: Z
authors.lastname: Wang
authors.forename: Shijuan
authors.initials: S
authors.lastname: Yan
authors.forename: Chunming
authors.initials: C
authors.lastname: Liu
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.forename: Tai
authors.initials: T
authors.lastname: Wang
mesh_terms: D016604:Aflatoxin B1 / Q000235:genetics / Q000276:immunology*; D010367:Arachis / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D001231:Aspergillus flavus / Q000472:pathogenicity*; D002473:Cell Wall; D003001:Cloning, Molecular; D018548:Cotyledon / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D018506:Gene Expression Regulation, Plant; D018525:Germination; D054884:Host-Pathogen Interactions; D025282:Mycelium / Q000254:growth & development / Q000276:immunology; D059828:Plant Cells / Q000276:immunology / Q000382:microbiology; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology; D057865:Plant Immunity; D020543:Proteome / Q000032:analysis*; D055314:Seed Storage Proteins / Q000276:immunology; D012639:Seeds / Q000276:immunology / Q000382:microbiology; D015398:Signal Transduction; D013045:Species Specificity
chemical_list: D020543:Proteome; D055314:Seed Storage Proteins; D016604:Aflatoxin B1