Molecular Plant-microbe Interactions最新文献

{"title":"WY-Slim Scaffolds: Modular Architecture of Conserved <i>Phytophthora</i> RxLR Effectors.","authors":"Nawaraj Dulal, Meenu Singla-Rastogi","doi":"10.1094/MPMI-01-26-0011-CM","DOIUrl":"https://doi.org/10.1094/MPMI-01-26-0011-CM","url":null,"abstract":"","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":"39 1","pages":"12-13"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147317677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural Insights into WY Domain SLiM-Containing Conserved RxLR Effectors: A Case Study of Five Important <i>Phytophthora</i> Species.","authors":"B C Salasini, J Chepsergon, C I Nxumalo, L N Moleleki","doi":"10.1094/MPMI-11-24-0144-R","DOIUrl":"10.1094/MPMI-11-24-0144-R","url":null,"abstract":"<p><p>Pathogenicity in <i>Phytophthora</i> species is in part underpinned by a sophisticated arsenal of RxLR effectors, which function as molecular determinants of host immune manipulation. Among these, conserved RxLR effectors (CREs) represent an evolutionarily conserved subset that is indispensable for virulence. However, the structural basis of their function remains poorly understood. Here, we conducted in silico analysis of CREs across five agriculturally significant <i>Phytophthora</i> species, revealing a conserved subset that integrates WY domains with embedded short linear motifs (SLiMs), a previously recognized architectural feature with functional implications. Notably, our findings indicate that despite the canonical association of SLiMs with intrinsically disordered regions, their incorporation within the structured WY domain preserves domain integrity while potentially expanding the effector's interactome within host cells. To explore the functional relevance of this domain organization, we characterized <i>Phytophthora nicotianae</i> RxLR6 (PpRxLR6), a representative WY-SLiM CRE identified in this study. Using <i>Agrobacterium</i>-mediated transient expression assays, we demonstrate that PpRxLR6 activates key immune defense networks in <i>Nicotiana</i> and <i>Solanum</i> species, suggesting a role in modulating host immune signaling. Structural predictions further reveal that PpRxLR6 harbors its SLiM within a well-ordered WY-like helical core region, suggesting that SLiM-mediated interactions may occur within structured effector domains rather than being confined to intrinsically disordered regions. These findings enhance our understanding of the effector domain architecture of PpRxLR6, illustrating how structured domains in CREs may serve as scaffolds for SLiM-mediated interactions. This structural arrangement may represent an adaptive strategy in <i>Phytophthora</i> evolution, potentially enhancing effector versatility in host interactions and immune modulation. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"14-30"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145286301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grapevines Pretreated with Biocontrol Bacteria Have an Altered Transcriptional Response to <i>Xylella fastidiosa</i> and a Reduction in Pierce's Disease Severity.","authors":"Elizabeth Deyett, Biagio DiSalvo, Mélanie Massonnet, Vanessa Ashworth, Dario Cantu, S Lindow, P E Rolshausen, M Caroline Roper","doi":"10.1094/MPMI-12-25-0166-R","DOIUrl":"10.1094/MPMI-12-25-0166-R","url":null,"abstract":"<p><p>In a previous DNA-based microbiome study of grapevines in areas of Pierce's disease (PD) pressure, we determined that taxa belonging to the <i>Pseudomonas</i> and <i>Achromobacter</i> genera negatively associated with PD severity and titer of the causal agent, <i>Xylella fastidiosa</i>, leading us to hypothesize that these taxa suppress PD and could be deployed as biocontrols. Here, we tested this hypothesis using two bacterial isolates from the grapevine endosphere, <i>Pseudomonas viridiflava</i> and <i>Achromobacter vitis</i>. We demonstrate that pretreatment with these two isolates significantly reduced PD symptoms and <i>X</i>. <i>fastidiosa</i> titer, comparable to that of a known PD biocontrol agent, <i>Paraburkholderia phytofirmans</i> PsJN. We monitored early spatial transcriptional responses using genome-wide transcriptional profiling in vines that were pretreated with the biocontrol strains and then inoculated with <i>X</i>. <i>fastidiosa.</i> We coupled this with phenotyping of internal tylose development and external disease symptoms and bacterial titer and determined that grapevines pretreated with the biocontrols <i>A</i>. <i>vitis</i> and PsJN developed fewer tyloses and PD symptoms and underwent major transcriptional reprogramming in response to <i>X</i>. <i>fastidiosa</i>. These included upregulation of genes in auxin- and ethylene-signaling pathways linked to tylose development. In contrast, <i>P</i>. <i>viridiflava</i> pretreatment also resulted in a reduction of tyloses and PD symptoms but did not induce major transcriptional changes in vines, suggesting that it likely has a direct inhibitory effect on <i>X</i>. <i>fastidiosa</i> through antibiosis. Using these data, we propose a model that incorporates timely and effective deployment of tyloses driven by induction of ethylene and auxin pathways as a key factor in PD resistance. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"114-126"},"PeriodicalIF":3.9,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145985171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural and Transcriptional Diversity in the Repertoire of <i>Sclerotinia sclerotiorum</i> Effector Candidates.","authors":"Darcy A B Jones, Sylvain Raffaele","doi":"10.1094/MPMI-08-25-0101-R","DOIUrl":"10.1094/MPMI-08-25-0101-R","url":null,"abstract":"<p><p>The necrotrophic fungal pathogen <i>Sclerotinia sclerotiorum</i> is distinguished by its exceptionally broad host range, infecting numerous plant species across diverse genera. Although historically characterized by a seemingly unspecialized infection strategy, increasing evidence indicates that <i>S</i>. <i>sclerotiorum</i> employs a diverse suite of virulence mechanisms, including effectors for host and environment manipulation. Leveraging recent advances in structural genomics and the growing availability of genomic and transcriptomic resources, we systematically re-examined the effector repertoire of the reference strain 1980 using updated computational approaches. We identified 215 effector-like proteins, which were classified into structural families based on predicted tertiary structures. Transcriptome meta-analysis across hundreds of publicly available samples revealed diverse expression patterns among effectors, highlighting both conserved and condition-specific expression dynamics. Several effector families were found to be expanded in <i>S</i>. <i>sclerotiorum</i>, including groups with predicted antimicrobial functions and unique domain architectures. Within families, structural and surface property variation suggests potential functional diversification. Furthermore, coexpression network analysis uncovered putative gene clusters that may operate synergistically with selected effectors. This work refines our understanding of effector diversity and organization in <i>S</i>. <i>sclerotiorum</i> and provides a framework for prioritizing candidates for functional studies, ultimately contributing to the broader understanding of effector evolution in generalist fungal pathogens. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"62-79"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145496154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single Amino Acid Change at Two Conserved Residues in Tomato Brown Rugose Fruit Virus Coat Protein Compromises Virion Assembly and Viral Systemic Infection.","authors":"Shaokang Zhang, Yinzi Li, Brian Weselowski, Jonathan S Griffiths, Xiuming Hao, Cara M McCreary, Mark A Bernards, Aiming Wang","doi":"10.1094/MPMI-07-25-0095-R","DOIUrl":"10.1094/MPMI-07-25-0095-R","url":null,"abstract":"<p><p><i>Tomato brown rugose fruit virus</i> (ToBRFV; <i>Tobamovirus fructirugosum</i>) is a recently discovered new species in the genus <i>Tobamovirus</i> that causes an ongoing pandemic and threatens tomato production worldwide. In this study, we determined the complete genome sequences of three ToBRFV isolates collected from greenhouse tomato plants in Canada in 2019, analyzed their possible phylogenetic relationships, and developed corresponding full-length infectious cDNA clones. Using the ToBRFV infectious clone, we generated gene-specific mutants via site-directed mutagenesis, followed by an infection assay. We confirmed that both the movement protein and the coat protein (CP) are indispensable for ToBRFV long-distance movement. Moreover, we found that alanine substitution of amino acid D89 or R114, both of which are highly conserved among tobamoviral CPs, compromised ToBRFV systemic infection. Confocal and electron microscopy analyses further revealed that either D89A or R114A substitution disrupted CP self-interactions and virion assembly. Additionally, we demonstrated that the ToBRFV 126-kDa replicase has RNA silencing suppression activity. Taken together, our data contribute to a better understanding of ToBRFV-encoded proteins at the molecular level, and the ToBRFV full-length infectious cDNA clones developed from this study are a useful tool to facilitate ToBRFV research. [Formula: see text] © 2026 His Majesty the King in Right of Canada, as represented by the Minister of Agriculture and Agri-Food Canada. This is an open access article distributed under the CC BY-NC-ND 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"31-44"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145496110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Novel Chitinase-Like Family of Candidate Effectors Unique to Aphids.","authors":"Rosa Lopez-Cobollo, Simone Altmann, Peter Thorpe, Nadine Douglas, Po-Yuan Shih, Laura Eccleston, Mark Lord, Eunji Hong, Emese Klug, Javaid Iqbal, Jorunn Bos, James Carolan, Colin Turnbull","doi":"10.1094/MPMI-08-25-0098-R","DOIUrl":"10.1094/MPMI-08-25-0098-R","url":null,"abstract":"<p><p>Molecular interactions between aphids and plants include delivery of salivary effector proteins into host cells, acting as virulence factors to suppress host immunity or as avirulence functions triggering immune activation. However, understanding of virulence and avirulence mechanisms in aphid-plant systems is currently limited. Here, we report the discovery of an effector candidate family that is unique to aphids. Using functional genomics data on divergent pea aphid (<i>Acyrthosiphon pisum</i>) genotypes and their F1 progeny, we filtered for differentially expressed saliva proteins that cosegregated with virulence or avirulence phenotypes. LOC100575698 (ACPISUM_029930), annotated as an uncharacterized protein, was the sole candidate effector for which RNA-seq and saliva proteomics data showed significantly different expression both between avirulent and virulent parents and between their segregating F1 progeny, with this gene upregulated in avirulent genotypes. BLASTP searches revealed multiple divergent homologs only in genomes of the Aphidomorpha infraorder, suggesting a hitherto undefined ancient aphid-specific gene family. AlphaFold models indicate strong structural similarities but weak sequence homology to chitinases. Because members of the aphid-specific clade all lack canonical DxxDxDxE motifs for catalytic activity, we designate the proteins as a novel chitinase-like (CHL) family. Association of ACPISUM_029930 (ApCHL1) with avirulence was further supported by cosegregating single-nucleotide polymorphisms and a genotype-specific alternatively spliced isoform. We hypothesize that CHL proteins may function similarly to phylogenetically unrelated chitin-binding fungal effectors that sequester chitin, also present in aphid stylets, potentially preventing defense activation through plant chitin receptors and/or blocking chitin degradation by host-secreted chitinases. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"102-113"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145409555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>MPMI</i> Acknowledgment of Reviewers, 2025.","authors":"","doi":"10.1094/MPMI-39-01-0003","DOIUrl":"https://doi.org/10.1094/MPMI-39-01-0003","url":null,"abstract":"","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":"39 1","pages":"3"},"PeriodicalIF":3.4,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147317559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population Genomics of <i>Macrophomina</i> spp. Reveals Cryptic Host Specialization and Evidence for Meiotic Recombination.","authors":"K K Pennerman, P Goldman, C J Dilla-Ermita, G Ramos, J H Jaime, J Lopez-Hernandez, J Ramos, M Aviles, C Borrero, A O Gomez, J M Neal, M Chilvers, V Ortiz, E H Stukenbrock, G H Goldman, A Mengitsu, H D Lopez-Nicora, G O Sacher, N Vaghefi, L Kiss, J P Benz, A R Machado, T E Seijo, N A Peres, F N Martin, J C Broome, K Ivors, G S Cole, S J Knapp, D J McFarlane, S W Mattner, M Gambardella, E Gluck-Thaler, P M Henry","doi":"10.1094/MPMI-03-25-0032-R","DOIUrl":"10.1094/MPMI-03-25-0032-R","url":null,"abstract":"<p><p>Knowledge of the factors structuring populations of pathogenic fungi is fundamental to disease management efforts and basic biology. However, this crucial information is missing for many important pathogens, including broad-host-range and drought-associated pathogens from the globally distributed <i>Macrophomina</i> genus. The objectives of this work were to evaluate the evidence for host specialization, geographic adaptation, and recombination using a global survey of <i>Macrophomina</i> isolates from diverse geographic, temporal, and host sources. We obtained high-quality short-read sequence data for 463 <i>Macrophomina</i> spp. isolates, representing four putative species, collected from 91 host plant species and soil in 23 countries. Analysis of bi-allelic, single-nucleotide polymorphisms revealed high diversity, admixture, and equal mating type ratios, suggesting ongoing recombination. Although most tested isolates asymptomatically colonized strawberry, only strawberry-derived isolates caused disease on this host. These isolates were all in a single lineage, suggesting that the ability to cause disease on strawberry is not widespread among <i>M. phaseolina</i>. Significant associations were also found between isolations from soybean plants and specific population clusters, suggesting that specialization for virulence or reproduction has also occurred for soybean. Geography × isolate genotype associations were weak, suggesting that <i>Macrophomina</i> spp. were frequently trafficked between regions. Reference-free whole-genome comparisons support current boundaries among four <i>Macrophomina</i> species, and new molecular markers were designed to specifically identify each species. Contrary to expectations, <i>M. phaseolina</i> should be considered a single species with both specialist and generalist populations in which meiosis can maintain genetic diversity. [Formula: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"925-938"},"PeriodicalIF":3.4,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144485182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stachydrine Catabolism Contributes to an Optimal Root Nodule Symbiosis Between <i>Sinorhizobium meliloti</i> and <i>Medicago sativa</i>.","authors":"Garrett J Levin, Jason V S Kearsley, Turlough M Finan, Barney A Geddes","doi":"10.1094/MPMI-02-25-0021-SC","DOIUrl":"10.1094/MPMI-02-25-0021-SC","url":null,"abstract":"<p><p><i>Sinorhizobium meliloti</i> forms a robust N₂-fixing root-nodule symbiosis with <i>Medicago sativa</i>. We are interested in identifying the minimal symbiotic genome of the model strain <i>S</i>. <i>meliloti</i> Rm1021. This gene set refers to the minimal genetic determinants required to form a robust N₂-fixing symbiosis. Many symbiotic genes are located on the 1,354-kb pSymA megaplasmid of <i>S</i>. <i>meliloti</i> Rm1021. We recently constructed a minimalized pSymA, minSymA2.1, that lacked over 90% of the pSymA genes. Relative to the wild type, minSymA2.1 showed a reduction in <i>M</i>. <i>sativa</i> shoot biomass production and nodule size with an increase in total nodule number. Here, we show that the addition of either the stachydrine (<i>stc</i>) or trigonelline (<i>trc</i>) catabolism genes from pSymA to minSymA2.1 restores nodule size and total nodule number to levels indistinguishable from the wild type but does not restore reduced shoot biomass production. In the context of the complete Rm1021 genome, removing the <i>stc</i> genes reduced the nodule size and increased the total nodule number, whereas removal of the <i>trc</i> genes alone had no apparent effect. Together, these observations implicate stachydrine catabolism as an important determinant of root nodule symbiosis between <i>S</i>. <i>meliloti</i> and <i>M</i>. <i>sativa</i>, whereas trigonelline catabolism seems to contribute in a more conditional manner, in the context of the minimized genome. These findings highlight the minimal symbiotic genome as a tool for investigating the impact of individual genetic determinants in conferring an optimal symbiosis, factors whose impact, in the context of a complete genome, may be hidden or dampened due to redundancies. [Formula: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"869-877"},"PeriodicalIF":3.4,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144817187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accelerated Haustoria Segmentation Enables Rapid Gene Function Analysis in Cereal-Powdery Mildew Pathosystems.","authors":"Stefanie Lück, Deniz Demirhan, Laura Agsten, Ahmed Raza Khan, Oksana Maier, Dimitar K Douchkov","doi":"10.1094/MPMI-06-25-0067-TA","DOIUrl":"10.1094/MPMI-06-25-0067-TA","url":null,"abstract":"<p><p>Reliable, high-throughput quantification of early fungal infection events is crucial for gene function studies, but it remains labor-intensive. We report an openly available pipeline that automates the detection of β-glucuronidase (GUS)-stained epidermal cells and the intracellular haustoria formed by powdery mildew on barley and wheat leaves. Whole-slide images are captured with a commercial scanner, focus-projected, tiled, and analyzed by deep-learning models trained on expertly annotated datasets. A <i>You Only Look Once</i> (<i>YOLO</i>) network identifies GUS-positive cells, and a companion segmentation model pinpoints haustoria within each cell; automatic focus-layer selection preserves fine structural detail. The workflow runs in minutes per slide on a single workstation and maintains near-perfect agreement with manual counts in both barley and wheat, demonstrating robust cross-species transferability. By delivering single-cell readouts with minimal user input, the pipeline enables rapid functional validation screens and supports large-scale phenotyping of cereal-powdery mildew interactions. [Formula: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.</p>","PeriodicalId":19009,"journal":{"name":"Molecular Plant-microbe Interactions","volume":" ","pages":"825-833"},"PeriodicalIF":3.4,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145125295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}