TY - JOUR T1 - Evolutionary trade-offs at the Arabidopsis <em>WRR4A</em> resistance locus underpin alternate <em>Albugo</em> candida recognition specificities JF - bioRxiv DO - 10.1101/2021.03.29.437434 SP - 2021.03.29.437434 AU - Baptiste Castel AU - Sebastian Fairhead AU - Oliver J. Furzer AU - Amey Redkar AU - Shanshan Wang AU - Volkan Cevik AU - Eric B. Holub AU - Jonathan D. G. Jones Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/03/29/2021.03.29.437434.abstract N2 - The oomycete Albugo candida causes white rust of Brassicaceae, including vegetable and oilseed crops, and wild relatives such as Arabidopsis thaliana. Novel White Rust Resistance (WRR)-genes from Arabidopsis enable new insights into plant/parasite co-evolution. WRR4A from Arabidopsis accession Col-0 provides resistance to many but not all white rust races, and encodes a nucleotide-binding (NB), leucine-rich repeat (LRR) (NLR) immune receptor protein. Col-0 WRR4A resistance is broken by a Col-0-virulent isolate of A. candida race 4 (AcEx1). We identified an allele of WRR4A in Arabidopsis accession Oy-0 and other accessions that confers full resistance to AcEx1. WRR4AOy-0 carries a C-terminal extension required for recognition of AcEx1, but reduces recognition of several effectors recognized by the WRR4ACol-0 allele. WRR4AOy-0 confers full resistance to AcEx1 when expressed as a transgene in the oilseed crop Camelina sativa.Significance A C-terminal extension in an allele of the Arabidopsis resistance-protein WRR4A changes effector recognition specificity, enabling the WRR4AOy-0 allele to confer immunity to Albugo candida races that overcome the WRR4ACol-0 allele. This resistance can be transferred to the oil-producing crop Camelina sativa.Competing Interest StatementThe authors have declared no competing interest. ER -