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Olave-Achury, A. C.

Publications and source records attributed to Olave-Achury, A. C..

2 recordsLinked to original sources

Diverse haplotypes at a complex Solanum americanum locus confer resistance to Phytophthora infestans and P. capsici

Plants encounter diverse pathogens and have evolved a two-layered innate immune system to detect pathogen molecules and activate defense mechanisms that restrict infection. Most cloned plant Resistance (R) genes encode NLR immune receptors. NLR genes are often found in clusters of paralogs with sequence and copy number variation; whether these NLR clusters evolve in response to single or multiple pathogens has been unclear. We report here the isolation of a Phytophthora capsici resistance gene, Rpc2, along with a novel P. infestans resistance gene, Rpi-amr5, from two Solanum americanum accessions. These orthologous genes reside in the Rpi-amr1 cluster, which has previously been associated with resistance to P. infestans. By screening RXLR effector libraries of P. infestans and P. capsici, we identified multiple effectors recognized by both NLRs. Our findings highlight the complexity of NLR clusters and evolution driven by interactions with multiple pathogens. This work will underpin efforts to elevate resistance against Phytophthora pathogens and enhances our understanding of NLR evolution.

plant biology↗

Effector-dependent activation and oligomerization of NRC helper NLRs by Rpi-amr3 and Rpi-amr1

Plant pathogens compromise crop yields. Plants have evolved robust innate immunity that depends in part on intracellular Nucleotide-binding, Leucine Rich-Repeat (NLR) immune receptors that activate defense responses upon detection of pathogen-derived effectors. Most "sensor" NLRs that detect effectors require the activity of "helper" NLRs, but how helper NLRs support sensor NLR function is poorly understood. Many Solanaceae NLRs require the NRC (NLR-Required for Cell death) class of helper NLRs. We show here that Rpi-amr3, a sensor NLR from Solanum americanum, detects AVRamr3 from the potato late blight pathogen, Phytophthora infestans, and activates oligomerization of the helper NLR NRC2 into a high-molecular weight resistosome. The NRC2 resistosome also forms upon recognition of P. infestans effector AVRamr1 by another sensor NLR, Rpi-amr1. The ATP-binding motif of Rpi-amr3 is required for NRC2 resistosome formation, but not for interaction with the cognate effector. The NRC2 resistosome can be activated by AVRamr3 homologs from other Phytophthora species. Mechanistic understanding of NRC resistosome formation will underpin engineering crops with durable disease resistance.

plant biology↗