title: Stabilization of cytokinin levels enhances Arabidopsis resistance against Verticillium longisporum.
abstract: Verticillium longisporum is a vascular pathogen that infects the Brassicaceae host plants Arabidopsis thaliana and Brassica napus. The soilborne fungus enters the plant via the roots and colonizes the xylem of roots, stems, and leaves. During late stages of infections, Verticillium spp. spread into senescing tissue and switch from biotrophic to a necrotrophic life style. Typical symptoms of V. longisporum-induced disease are stunted growth and leaf chlorosis. Expression analyses of the senescence marker genes SENESCENCE-ASSOCIATED GENE12, SENESCENCE-ASSOCIATED GENE13, and WRKY53 revealed that the observed chlorosis is a consequence of premature senescence triggered by Verticillium infection. Our analyses show that, concomitant with the development of chlorosis, levels of trans-zeatin decrease in infected plants. Potentially, induction of cytokinin oxidase/dehydrogenase expression by Verticillium infection contributes to the observed decreases in cytokinin levels. Stabilization of Arabidopsis cytokinin levels by both pharmacological and genetic approaches inhibits Verticillium proliferation and coincides with reduced disease symptom development. In summary, our results indicate that V. longisporum triggers premature plant senescence for efficient host plant colonization.
authors.affiliation: Georg-August-University, Gottingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Reusche
authors.forename: Jana
authors.initials: J
authors.lastname: Klásková
authors.forename: Karin
authors.initials: K
authors.lastname: Thole
authors.forename: Jekaterina
authors.initials: J
authors.lastname: Truskina
authors.forename: Ondřej
authors.initials: O
authors.lastname: Novák
authors.forename: Dennis
authors.initials: D
authors.lastname: Janz
authors.forename: Miroslav
authors.initials: M
authors.lastname: Strnad
authors.forename: Lukáš
authors.initials: L
authors.lastname: Spíchal
authors.forename: Volker
authors.initials: V
authors.lastname: Lipka
authors.forename: Thomas
authors.initials: T
authors.lastname: Teichmann
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000494:pharmacology; D017360:Arabidopsis / Q000378:metabolism* / Q000382:microbiology*; D003583:Cytokinins / Q000235:genetics / Q000378:metabolism*; D004271:DNA, Fungal / Q000302:isolation & purification / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology*; D013997:Time Factors; D020172:Verticillium / Q000502:physiology*
chemical_list: C580806:2-chloro-6-(3-methoxyphenyl)aminopurine; D003583:Cytokinins; D004271:DNA, Fungal; D000225:Adenine