Abstract Detail

Symbioses: Plant, Animal, and Microbe Interactions

Tu, Jiangying [1], Bonham-Smith, Peta [1], Wei, Yangdou [1].

PIN-mediated auxin transport modulates clubroot disease symptom development during the Arabidopsis-Plasmodiophora interaction.

Plasmodiophora brassicae is the causal agent of clubroot in the agriculturally important Brassicaceae family. Clubroot disease is characterized by root swellings that are believed to be caused by the alteration of auxin and/or cytokinin metabolism in infected cells. Intercellular transport of auxin is essential for various aspects of plant growth and development. A holistic approach was undertaken to understand the role of auxin transporters in early clubroot development. To study the effects of this interaction a new model Arabidopsis-P. brassicae pathosystem was established. Using a set of PINx-GFP fusion lines; PIN1-GFP, PIN2-GFP, PIN3-GFP, PIN4-GFP, and PIN7-GFP, both spatial and temporal expression of auxin transporters has been studied during the early stage of P. brassicae infection. At the same time, T-DNA knockdown mutants of the individual auxin transporters; PIN1, PIN2, PIN3, PIN4 and PIN7, were screened and infected in order to determine possible roles for the different PIN proteins during P. brassicae infection and clubroot progression. Preliminary data suggests that auxin efflux transport mediated by PIN2 is blocked in infected root cells and that the pin2 mutant is more tolerant to clubroot than wild type Arabidopsis. We hypothesize that P. brassicae infection disrupts auxin homeostasis in infected root cells, and increased auxin levels in infected cells promote the development of clubroot symptoms during the Arabidopsis-Plasmodiophora interaction. In the pin2 mutant, it is unlikely that auxin can reach the site of infection, underlining the need for appropriate auxin transport for gall formation.

1 - University of Saskatchewan, Department of Biology, 112 science place, biology building, Saskatoon, SK, Canada

Keywords:
Plasmodiophora brassicae
Clubroot
Auxin transport
Arabidopsis.

Presentation Type: Oral Paper:Papers for Topics
Session: 51
Location: Salon 5/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 4:30 PM
Number: 51012
Abstract ID:514
Candidate for Awards:None