אסיף מאגר המחקר החקלאי

The Arabidopsis Rho of plants GTPase AtROP6 functions in developmental and pathogen response pathways

Year:

2013

Source of publication :

Authors :

Volume :

161

Co-Authors:

Poraty-Gavra, L., Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv 69978, Israel
Zimmermann, P., Department of Biology, Eidgenössisch Technische Hochschule, Zurich CH-8092, Switzerland
Haigis, S., Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding, Cologne D-50829, Germany
Bednarek, P., Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding, Cologne D-50829, Germany
Hazak, O., Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv 69978, Israel
Stelmakh, O.R., Department of Ornamental Horticulture, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Sadot, E., Department of Ornamental Horticulture, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Schulze-Lefert, P., Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding, Cologne D-50829, Germany
Gruissem, W., Department of Biology, Eidgenössisch Technische Hochschule, Zurich CH-8092, Switzerland
Yalovsky, S., Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv 69978, Israel

Facilitators :

Link :

Abstract:

How plants coordinate developmental processes and environmental stress responses is a pressing question. Here, we show that Arabidopsis (Arabidopsis thaliana) Rho of Plants6 (AtROP6) integrates developmental and pathogen response signaling. AtROP6 expression is induced by auxin and detected in the root meristem, lateral root initials, and leaf hydathodes. Plants expressing a dominant negative AtROP6 (rop6DN) under the regulation of its endogenous promoter are small and have multiple inflorescence stems, twisted leaves, deformed leaf epidermis pavement cells, and differentially organized cytoskeleton. Microarray analyses of rop6DN plants revealed that major changes in gene expression are associated with constitutive salicylic acid (SA)-mediated defense responses. In agreement, their free and total SA levels resembled those of wild-type plants inoculated with a virulent powdery mildew pathogen. The constitutive SA-associated response in rop6DN was suppressed in mutant backgrounds defective in SA signaling (nonexpresser of PR genes1 [npr1]) or biosynthesis (salicylic acid induction deficient2 [sid2]). However, the rop6DN npr1 and rop6DN sid2 double mutants retained the aberrant developmental phenotypes, indicating that the constitutive SA response can be uncoupled from ROP function(s) in development. rop6DN plants exhibited enhanced preinvasive defense responses to a host-adapted virulent powdery mildew fungus but were impaired in preinvasive defenses upon inoculation with a nonadapted powdery mildew. The host-adapted powdery mildew had a reduced reproductive fitness on rop6DN plants, which was retained in mutant backgrounds defective in SA biosynthesis or signaling. Our findings indicate that both the morphological aberrations and altered sensitivity to powdery mildews of rop6DN plants result from perturbations that are independent from the SA-associated response. These perturbations uncouple SA-dependent defense signaling from disease resistance execution. © 2013 American Society of Plant Biologists. All Rights Reserved.

Note:

Related Files :

Related Content

More details

You may also be interested in