The B-3 Ethylene Response Factor MtERF1-1 Mediates Resistance to a Subset of Root Pathogens inMedicago truncatulawithout Adversely Affecting Symbiosis with Rhizobia
Open Access
- 16 August 2010
- journal article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 154 (2), 861-873
- https://doi.org/10.1104/pp.110.163949
Abstract
The fungal necrotrophic pathogen Rhizoctonia solani is a significant constraint to a range of crops as diverse as cereals, canola, and legumes. Despite wide-ranging germplasm screens in many of these crops, no strong genetic resistance has been identified, suggesting that alternative strategies to improve resistance are required. In this study, we characterize moderate resistance to R. solani anastomosis group 8 identified in Medicago truncatula. The activity of the ethylene- and jasmonate-responsive GCC box promoter element was associated with moderate resistance, as was the induction of the B-3 subgroup of ethylene response transcription factors (ERFs). Genes of the B-1 subgroup showed no significant response to R. solani infection. Overexpression of a B-3 ERF, MtERF1-1, in Medicago roots increased resistance to R. solani as well as an oomycete root pathogen, Phytophthora medicaginis, but not root knot nematode. These results indicate that targeting specific regulators of ethylene defense may enhance resistance to an important subset of root pathogens. We also demonstrate that overexpression of MtERF1-1 enhances disease resistance without apparent impact on nodulation in the A17 background, while overexpression in sickle reduced the hypernodulation phenotype. This suggests that under normal regulation of nodulation, enhanced resistance to root diseases can be uncoupled from symbiotic plant-microbe interactions in the same tissue and that ethylene/ERF regulation of nodule number is distinct from the defenses regulated by B-3 ERFs. Furthermore, unlike the stunted phenotype previously described for Arabidopsis (Arabidopsis thaliana) ubiquitously overexpressing B-3 ERFs, overexpression of MtERF1-1 in M. truncatula roots did not show adverse effects on plant development.Keywords
This publication has 45 references indexed in Scilit:
- Elicitor-induced transcription factors for metabolic reprogramming of secondary metabolism in Medicago truncatulaBMC Plant Biology, 2008
- A community resource for high-throughput quantitative RT-PCR analysis of transcription factor gene expression in Medicago truncatulaPlant Methods, 2008
- The AP2/ERF Domain Transcription Factor ORA59 Integrates Jasmonic Acid and Ethylene Signals in Plant DefensePlant Physiology, 2008
- RL-SAGE and microarray analysis of the rice transcriptome after Rhizoctonia solani infectionMolecular Genetics and Genomics, 2007
- An ERF Transcription Factor in Medicago truncatula That Is Essential for Nod Factor Signal TransductionPlant Cell, 2007
- Involvement of the Octadecanoid Pathway in Bluegreen Aphid Resistance in Medicago truncatulaMolecular Plant-Microbe Interactions®, 2007
- AtERF14, a Member of the ERF Family of Transcription Factors, Plays a Nonredundant Role in Plant DefensePlant Physiology, 2006
- Emerging infectious diseases of plants: pathogen pollution, climate change and agrotechnology driversTrends in Ecology & Evolution, 2004
- Early Induction of the Arabidopsis GSTF8 Promoter by Specific Strains of the Fungal Pathogen Rhizoctonia solaniMolecular Plant-Microbe Interactions®, 2004
- Confidence Limits on Phylogenies: An Approach Using the BootstrapEvolution, 1985