title: Microarray analysis shows that recessive resistance to Watermelon mosaic virus in melon is associated with the induction of defense response genes.
abstract: Resistance to Watermelon mosaic virus (WMV) in melon (Cucumis melo L.) accession TGR-1551 is characterized by a significant reduction in virus titer, and is inherited as a recessive, loss-of-susceptibility allele. We measured virus RNA accumulation in TGR-1551 plants and a susceptible control ('Tendral') by real-time quantitative polymerase chain reaction, and also profiled the expression of 17,443 unigenes represented on a melon microarray over a 15-day time course. The virus accumulated to higher levels in cotyledons of the resistant variety up to 9 days postinoculation (dpi) but, thereafter, levels increased in the susceptible variety while those in the resistant variety declined. Microarray experiments looking at the early response to infection (1 and 3 dpi), as well as responses after 7 and 15 dpi, revealed more profound transcriptomic changes in resistant plants than susceptible ones. The gene expression profiles revealed deep and extensive transcriptome remodeling in TGR-1551 plants, often involving genes with pathogen response functions. Overall, our data suggested that resistance to WMV in TGR-1551 melon plants is associated with a defense response, which contrasts with the recessive nature of the resistance trait.
authors.affiliation: Departamento de Biologia del Estres y Patologia Vegetal, Centro de Edafologia y Biologia Aplicada de Segura, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Gonzalez-Ibeas
authors.forename: Joaquin
authors.initials: J
authors.lastname: Cañizares
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Aranda
mesh_terms: D029773:Citrullus / Q000821:virology; D016000:Cluster Analysis; D018548:Cotyledon / Q000235:genetics / Q000821:virology; D028463:Cucumis melo / Q000235:genetics* / Q000276:immunology / Q000821:virology; D020869:Gene Expression Profiling; D017343:Genes, Plant / Q000235:genetics; D005838:Genotype; D058977:Molecular Sequence Annotation; D020411:Oligonucleotide Array Sequence Analysis; D010935:Plant Diseases / Q000821:virology*; D057865:Plant Immunity; D017800:Potyvirus / Q000502:physiology*; D018749:RNA, Plant / Q000235:genetics; D036226:Seedlings / Q000235:genetics / Q000276:immunology / Q000821:virology; D013997:Time Factors; D015533:Transcriptional Activation / Q000235:genetics; D059467:Transcriptome / Q000235:genetics*; D019562:Viral Load
chemical_list: D018749:RNA, Plant