The plant immune system: From discovery to deployment

Cell, Год журнала: 2024, Номер 187(9), С. 2095 - 2116

Опубликована: Апрель 1, 2024

Plant diseases cause famines, drive human migration, and present challenges to agricultural sustainability as pathogen ranges shift under climate change. breeders discovered Mendelian genetic loci conferring disease resistance specific isolates over 100 years ago. Subsequent breeding for underpins modern agriculture and, along with the emergence focus on model plants genetics genomics research, has provided rich resources molecular biological exploration last 50 years. These studies led identification of extracellular intracellular receptors that convert recognition microbe-encoded patterns or pathogen-delivered virulence effectors into defense activation. receptor systems, downstream responses, define plant immune systems have evolved since migration land ∼500 million Our current understanding provides platform development rational enhancement control many continue plague crop production.

Язык: Английский

---

Plant NLR immunity activation and execution: a biochemical perspective

Open Biology, Год журнала: 2024, Номер 14(1)

Опубликована: Янв. 1, 2024

Plants deploy cell-surface and intracellular receptors to detect pathogen attack trigger innate immune responses. Inside host cells, families of nucleotide-binding/leucine-rich repeat (NLR) proteins serve as sensors or downstream mediators defence outputs cell death, which prevent disease. Established genetic underpinnings NLR-mediated immunity revealed various strategies plants adopt combat rapidly evolving microbial pathogens. The molecular mechanisms NLR activation signal transmission components controlling execution were less clear. Here, we review recent protein structural biochemical insights plant sensor signalling functions. When put together, the data show how different families, whether transducers, converge on nucleotide-based second messengers cellular calcium confer immunity. Although pathogen-activated NLRs in engage plant-specific machineries promote defence, comparisons with mammalian receptor counterparts highlight some shared working principles for across kingdoms.

Язык: Английский

---

Barley MLA3 recognizes the host-specificity effector Pwl2 from Magnaporthe oryzae

The Plant Cell, Год журнала: 2023, Номер 36(2), С. 447 - 470

Опубликована: Окт. 11, 2023

Abstract Plant nucleotide-binding leucine-rich repeat (NLRs) immune receptors directly or indirectly recognize pathogen-secreted effector molecules to initiate plant defense. Recognition of multiple pathogens by a single NLR is rare and usually occurs via monitoring for changes host proteins; few characterized NLRs have been shown effectors. The barley (Hordeum vulgare) gene Mildew locus (Mla) has undergone functional diversification, the proteins encoded different Mla alleles host-adapted isolates powdery mildew (Blumeria graminis f. sp. hordei [Bgh]). Here, we show that Mla3 also confers resistance rice blast fungus Magnaporthe oryzae in dosage-dependent manner. Using forward genetic screen, discovered recognized from M. Pathogenicity toward Weeping Lovegrass 2 (Pwl2), range determinant factor prevents infecting weeping lovegrass (Eragrostis curvula). therefore convergently evolved capacity effectors diverse pathogens.

Язык: Английский

---

Avirulence depletion assay: Combining R gene-mediated selection with bulk sequencing for rapid avirulence gene identification in wheat powdery mildew

PLoS Pathogens, Год журнала: 2025, Номер 21(1), С. e1012799 - e1012799

Опубликована: Янв. 7, 2025

Wheat production is threatened by multiple fungal pathogens, such as the wheat powdery mildew fungus ( Blumeria graminis f. sp. tritici , Bgt ). resistance breeding frequently relies on use of R ) genes that encode diverse immune receptors which detect specific avirulence AVR effectors and subsequently induce an response. While gene cloning has accelerated recently, identification in many pathogens including lags behind, preventing pathogen-informed deployment sources. Here we describe a new “avirulence depletion (AD) assay” for rapid . This assay selection segregating, haploid F1 progeny population resistant host, followed bulk sequencing, thereby allowing candidate with high mapping resolution. In proof-of-concept experiment mapped component receptor Pm3a to 25 kb genomic interval harboring single effector, previously described AvrPm3 a2/f2 Subsequently, applied AD map unknown effector recognized Pm60 receptor. We show AvrPm60 encoded three tandemly arrayed, nearly identical trigger response upon co-expression its alleles Pm60a Pm60b furthermore provide evidence outperforms through more efficient recognition effectors, suggesting it should be prioritized breeding. Finally, virulence towards caused simultaneous deletion all paralogs isolates lacking are especially prevalent US limiting potential this region. The powerful tool inexpensive contribute decisions novel regionally tailored deployment.

Язык: Английский

---

The structural landscape and diversity of Pyricularia oryzae MAX effectors revisited

PLoS Pathogens, Год журнала: 2024, Номер 20(5), С. e1012176 - e1012176

Опубликована: Май 6, 2024

Magnaporthe AVRs and ToxB-like (MAX) effectors constitute a family of secreted virulence proteins in the fungus Pyricularia oryzae (syn . oryzae) , which causes blast disease on numerous cereals grasses. In spite high sequence divergence, MAX share common fold characterized by ß-sandwich core stabilized conserved disulfide bond. this study, we investigated structural landscape diversity within effector repertoire P Combining experimental protein structure determination silico modeling validated presence domain 77 out 94 groups orthologs (OG) identified previous population genomic study. Four novel structures determined NMR were remarkably good agreement with AlphaFold2 (AF2) predictions. Based comparison AF2-generated 3D models propose classification superfamily 20 that vary canonical fold, bond patterns, additional secondary N- C-terminal extensions. About one-third members remain singletons, without strong relationship to other effectors. Analysis surface properties AF2 also highlights variability at level, potentially reflecting wide their functions host targets.

Язык: Английский

---

Decoding the Arsenal: Protist Effectors and Their Impact on Photosynthetic Hosts

Molecular Plant-Microbe Interactions, Год журнала: 2024, Номер 37(6), С. 498 - 506

Опубликована: Март 29, 2024

Interactions between various microbial pathogens including viruses, bacteria, fungi, oomycetes, and their plant hosts have traditionally been the focus of phytopathology. In recent years, a significant growing interest in study eukaryotic microorganisms not classified among fungi or oomycetes has emerged. Many these protists establish complex interactions with photosynthetic hosts, understanding is crucial dynamics parasites within traditional emerging types farming, marine aquaculture. phytopathogenic are biotrophs polyphasic life cycles, which makes them difficult impossible to culture, fact reflected wide gap availability comprehensive genomic data when compared fungal oomycete pathogens. Furthermore, our ability use available resources for limited by broad taxonomic distance that organisms span, comparisons other datasets difficult. The current rapid progress genomics computational tools prediction protein functions revolutionizing landscape pathology. This also opening novel possibilities, specifically deeper protist effectors. Tools like AlphaFold2 enable structure-based function effector candidates divergent sequences. turn, this allows us ask better biological questions and, coupled innovative experimental strategies, will lead into new era research, especially protists, expand knowledge on elusive hosts. [Formula: see text] Copyright © 2024 Author(s). an open access article distributed under CC BY-NC-ND 4.0 International license .

Язык: Английский

---

Powdery mildew effectors AVR_A1 and BEC1016 target the ER J‐domain protein HvERdj3B required for immunity in barley

Molecular Plant Pathology, Год журнала: 2024, Номер 25(5)

Опубликована: Май 1, 2024

The barley powdery mildew fungus, Blumeria hordei (Bh), secretes hundreds of candidate secreted effector proteins (CSEPs) to facilitate pathogen infection and colonization. One these, CSEP0008, is directly recognized by the nucleotide-binding leucine-rich-repeat (NLR) receptor MLA1 therefore designated AVR

Язык: Английский

---

Molecular mimicry of a pathogen virulence target by a plant immune receptor

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Июль 26, 2024

Abstract Plants and animals respond to pathogen attack by mounting innate immune responses that require intracellular nucleotide binding leucine-rich repeat (NLR) proteins. These receptors detect infection sensing virulence effector However, the mechanisms which evolve new recognition specificities remain poorly understood. Here we report a plant NLR has evolved capacity bind acting as molecular mimic of target effector, thereby triggering an response. The barley Mildew Locus A 3 (MLA3) confers resistance blast fungus Magnaporthe oryzae recognizing Pwl2. Using structural analysis, show MLA3 acquired Pwl2 through mimicry host HIPP43. We demonstrate amino acids at interface are highly conserved in HIPP43 with Pwl2, required trigger used this discovery bioengineer SR50—an MLA ortholog rye wheat stem rust—by introducing MLA3. This chimeric receptor dual activities, responding effectors from two major cereal pathogens. Collectively, these results provide evidence have sophisticated strategies counteract attack.

Язык: Английский

---

The barley MLA13-AVR_A13heterodimer reveals principles for immunoreceptor recognition of RNase-like powdery mildew effectors

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Июль 17, 2024

Abstract Co-evolution between cereals and pathogenic grass powdery mildew fungi is exemplified by sequence diversification of an allelic series barley resistance genes encoding Mildew Locus A (MLA) nucleotide-binding leucine-rich repeat (NLR) immunoreceptors with a N-terminal coiled-coil domain (CNLs). Each immunoreceptor recognises matching, strain-specific effector encoded avirulence gene ( AVR ) . We present here the cryo-EM structure MLA13 in complex its cognate A13 -1. The adopts RNase-like fold when bound to planta , similar crystal structures other e ffectors purified from E. coli -1 interacts via basal loops C-terminal leucine rich repeats (LRRs) central winged helix (WHD). Co-expression structure-guided substitution variants show that receptor–effector interface plays essential role mediating immunity-associated plant cell death. Furthermore, combining structural information MLA13–AVR heterocomplex alignments MLA receptors, we designed single amino acid MLA7 enables expanded detection virulent variant -V2. In contrast pentameric conformation previously reported effector-activated CNL resistosomes, was resolved as stable heterodimer expression system. Our study suggests might represent output distinct resistosomes highlights opportunities for development designer gain-of-function NLRs.

Язык: Английский

---

AvrSr27 is a zinc‐bound effector with a modular structure important for immune recognition

New Phytologist, Год журнала: 2024, Номер 243(1), С. 314 - 329

Опубликована: Май 10, 2024

Summary Effector proteins are central to the success of plant pathogens, while immunity in host plants is driven by receptor‐mediated recognition these effectors. Understanding molecular details effector–receptor interactions key for engineering novel immune receptors. Here, we experimentally determined crystal structure Puccinia graminis f. sp. tritici ( Pgt ) effector AvrSr27, which was not accurately predicted using AlphaFold2. We characterised role conserved cysteine residues AvrSr27 vitro biochemical assays and examined Sr27‐mediated transient expression Nicotiana spp. wheat protoplasts. The contains a β‐strand rich modular fold consisting two structurally similar domains that bind Zn 2+ ions. N‐terminal domain sufficient interaction with Sr27 triggering cell death. identified related but low sequence identity can also associate Sr27, albeit more weakly. Though only full‐length proteins, trigger Sr27‐dependent death systems. Collectively, our findings have important implications utilising protein prediction platforms those embarking on bespoke receptors as solutions disease.

Язык: Английский

---