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: Michael Reusche, Jana Klásková, Karin Thole, Jekaterina Truskina, Ondřej Novák, Dennis Janz, Miroslav Strnad, Lukáš Spíchal, Volker Lipka, Thomas Teichmann
• Journal: Molecular plant-microbe interactions : MPMI (Mol Plant Microbe Interact) Vol. 26 Issue 8 Pg. 850-60 (Aug 2013) ISSN: 0894-0282 [Print] United States
• PMID: 23594348 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• 2-chloro-6-(3-methoxyphenyl)aminopurine
• Cytokinins
• DNA, Fungal
• Adenine

Topics

• Adenine (analogs & derivatives, pharmacology)
• Arabidopsis (metabolism, microbiology)
• Cytokinins (genetics, metabolism)
• DNA, Fungal (isolation & purification, metabolism)
• Gene Expression Regulation, Plant (drug effects, physiology)
• Plant Diseases (microbiology)
• Time Factors
• Verticillium (physiology)