title: Cisgenic Rvi6 scab-resistant apple lines show no differences in Rvi6 transcription when compared with conventionally bred cultivars.
abstract: The expression of the apple scab resistance gene Rvi6 in different apple cultivars and lines is not modulated by biotic or abiotic factors. All commercially important apple cultivars are susceptible to Venturia inaequalis, the causal organism of apple scab. A limited number of apple cultivars were bred to express the resistance gene Vf from the wild apple genotype Malus floribunda 821. Positional cloning of the Vf locus allowed the identification of the Rvi6 (formerly HcrVf2) scab resistance gene that was subsequently used to generate cisgenic apple lines. It is important to understand and compare how this resistance gene is transcribed and modulated during infection in conventionally bred cultivars and in cisgenic lines. The aim of this work was to study the transcription pattern of Rvi6 in three classically bred apple cultivars and six lines of 'Gala' genetically modified to express Rvi6. Rvi6 transcription was analyzed at two time points using quantitative real-time PCR (RT-qPCR) following inoculation with V. inaequalis conidia or water. Rvi6 transcription was assessed in relation to five reference genes. β-Actin, RNAPol, and UBC were the most suited to performing RT-qPCR experiments on Malus × domestica. Inoculation with V. inaequalis conidia under conditions conducive to scab infection failed to produce any significant changes to the transcription level of Rvi6. Rvi6 expression levels were inconsistent in response to external treatments in the different apple cultivars, and transgenic, intragenic or cisgenic lines.
authors.affiliation: Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitaetstrasse 2, 8092, Zurich, Switzerland. cornelia.chizzali@leibniz-hki.de.|Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745, Jena, Germany. cornelia.chizzali@leibniz-hki.de.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Chizzali
authors.affiliation: Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitaetstrasse 2, 8092, Zurich, Switzerland.
authors.forename: Michele
authors.initials: M
authors.lastname: Gusberti
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research Centre, PO Box 16, 6700 AA, Wageningen, The Netherlands.
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Schouten
authors.affiliation: Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitaetstrasse 2, 8092, Zurich, Switzerland.
authors.forename: Cesare
authors.initials: C
authors.lastname: Gessler
authors.affiliation: Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitaetstrasse 2, 8092, Zurich, Switzerland.|Agroscope, Institute for Plant Production Sciences, Schloss 1, 8820, Wädenswil, Switzerland.
authors.forename: Giovanni A L
authors.initials: GA
authors.lastname: Broggini
mesh_terms: D000199:Actins / Q000235:genetics; D001203:Ascomycota / Q000502:physiology*; D001947:Breeding; D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D056426:Genetic Loci / Q000235:genetics; D005838:Genotype; D027845:Malus / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D057865:Plant Immunity / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified; D013172:Spores, Fungal
chemical_list: D000199:Actins; D010940:Plant Proteins; D012321:DNA-Directed RNA Polymerases
keywords: Apple scab; Cisgenic; Malus × domestica; Reference genes; Rvi6; Venturia inaequalis