6Q76

Complex of rice blast (Magnaporthe oryzae) effector protein AVR-Pia with the HMA domain of Pikp-1 from rice (Oryza sativa)

Summary for 6Q76

• Entry DOI: 10.2210/pdb6q76/pdb
• Descriptor: Resistance protein Pikp-1, AVR-Pia protein (3 entities in total)
• Functional Keywords: effector, heavy metal-associated, nlr, max, antifungal protein
• Biological source: Oryza sativa subsp. japonica (Rice); More
• Total number of polymer chains: 2
• Total formula weight: 15406.88

Authors

Varden, F.A.,Banfield, M.J. (deposition date: 2018-12-12, release date: 2019-07-10, Last modification date: 2024-01-24)

Primary citation

Varden, F.A.,Saitoh, H.,Yoshino, K.,Franceschetti, M.,Kamoun, S.,Terauchi, R.,Banfield, M.J.
Cross-reactivity of a rice NLR immune receptor to distinct effectors from the rice blast pathogenMagnaporthe oryzaeprovides partial disease resistance.
J.Biol.Chem., 294:13006-13016, 2019

PubMed Abstract: Unconventional integrated domains in plant intracellular immune receptors of the nucleotide-binding leucine-rich repeat (NLRs) type can directly bind translocated effector proteins from pathogens and thereby initiate an immune response. The rice () immune receptor pairs Pik-1/Pik-2 and RGA5/RGA4 both use integrated heavy metal-associated (HMA) domains to bind the effectors AVR-Pik and AVR-Pia, respectively, from the rice blast fungal pathogen These effectors both belong to the MAX effector family and share a core structural fold, despite being divergent in sequence. How integrated domains in NLRs maintain specificity of effector recognition, even of structurally similar effectors, has implications for understanding plant immune receptor evolution and function. Here, using plant cell death and pathogenicity assays and protein-protein interaction analyses, we show that the rice NLR pair Pikp-1/Pikp-2 triggers an immune response leading to partial disease resistance toward the "mis-matched" effector AVR-Pia and that the Pikp-HMA domain binds AVR-Pia We observed that the HMA domain from another Pik-1 allele, Pikm, cannot bind AVR-Pia, and it does not trigger a plant response. The crystal structure of Pikp-HMA bound to AVR-Pia at 1.9 Å resolution revealed a binding interface different from those formed with AVR-Pik effectors, suggesting plasticity in integrated domain-effector interactions. The results of our work indicate that a single NLR immune receptor can bait multiple pathogen effectors via an integrated domain, insights that may enable engineering plant immune receptors with extended disease resistance profiles.

PubMed: 31296569
DOI: 10.1074/jbc.RA119.007730

Experimental method

X-RAY DIFFRACTION (1.9 Å)