The Brassica napus blackleg resistance gene LepR3 encodes a receptor-like protein triggered by the Leptosphaeria maculans effector AVRLM1
Article first published online: 3 DEC 2012
© 2012 AAFC New Phytologist © 2012 New Phytologist Trust
Volume 197, Issue 2, pages 595–605, January 2013
How to Cite
Larkan, N. J., Lydiate, D. J., Parkin, I. A. P., Nelson, M. N., Epp, D. J., Cowling, W. A., Rimmer, S. R. and Borhan, M. H. (2013), The Brassica napus blackleg resistance gene LepR3 encodes a receptor-like protein triggered by the Leptosphaeria maculans effector AVRLM1. New Phytologist, 197: 595–605. doi: 10.1111/nph.12043
- Issue published online: 18 DEC 2012
- Article first published online: 3 DEC 2012
- Manuscript Accepted: 5 OCT 2012
- Manuscript Received: 31 JUL 2012
- Australian Research Council project. Grant Number: LP0210571
- Arabidopsis thaliana ;
- blackleg resistance;
- Brassica napus (canola/oilseed rape);
- Brassica rapa ;
- Leptosphaeria maculans ;
- receptor-like protein
- LepR3, found in the Brassica napus cv ‘Surpass 400’, provides race-specific resistance to the fungal pathogen Leptosphaeria maculans, which was overcome after great devastation in Australia in 2004. We investigated the LepR3 locus to identify the genetic basis of this resistance interaction.
- We employed a map-based cloning strategy, exploiting collinearity with the Arabidopsis thaliana and Brassica rapa genomes to enrich the map and locate a candidate gene. We also investigated the interaction of LepR3 with the L. maculans avirulence gene AvrLm1 using transgenics.
- LepR3 was found to encode a receptor-like protein (RLP). We also demonstrated that avirulence towards LepR3 is conferred by AvrLm1, which is responsible for both the Rlm1 and LepR3-dependent resistance responses in B. napus.
- LepR3 is the first functional B. napus disease resistance gene to be cloned. AvrLm1's interaction with two independent resistance loci, Rlm1 and LepR3, highlights the need to consider redundant phenotypes in ‘gene-for-gene’ interactions and offers an explanation as to why LepR3 was overcome so rapidly in parts of Australia.