{
  "abstract": "IntroductionWhile the pear canker pathogen Valsa pyri typically employs cell wall-degrading enzymes to breach host barriers, the functions of its glycoside hydrolase family 43 (GH43) proteins remain largely unexplored.MethodsHere, using genetic manipulation, secretion assays, transient-expression assays, and transcriptomic analysis, we investigated whether the GH43 protein VpGHa1 contributes to fungal virulence, stress adaptation, and suppression of host immunity.ResultsVpGHa1 contains a predicted signal peptide and a GH43_AnAbnA-like domain. VpGHa1 expression was strongly induced during the early stages of infection, and the protein was confirmed to be secreted. Sequence analysis predicted an endo-1,5-α-L-arabinofuranosidase-related function, and recombinant VpGHa1 showed positive anti-arabinase immunoreactivity in an antibody-based ELISA. Deletion of VpGHa1 reduced lesion size on pear twigs by 33.8%, whereas genetic complementation significantly restored the reduced-virulence phenotype and overexpression enhanced pathogenicity without affecting vegetative growth. The ΔVpGHa1 mutant showed increased tolerance to KCl but greater sensitivity to NaCl and H₂O₂, indicating that VpGHa1 contributes to ionic and oxidative stress adaptation. Furthermore, transient expression of VpGHa1 in Nicotiana benthamiana suppressed BAX- and INF1-induced cell death, promoted colonization by Sclerotinia sclerotiorum, and enhanced lesion formation after V. pyri challenge in apple leaves; this was accompanied by downregulation of apple defense-related genes. Transcriptomic analysis identified 115 DEGs between the WT and ΔVpGHa1 mutant and revealed enrichment of carbohydrate-related, extracellular/cell-surface-associated, and metabolic processes, suggesting broad transcriptional effects associated with cell-surface and metabolic adaptation.DiscussionTogether, these findings identify VpGHa1 as a multifunctional secreted GH43 virulence factor linking pathogenicity, stress adaptation, and host immune suppression, whereas its predicted arabinan-related enzymatic activity remains to be experimentally validated.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Original Research",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "Shasha Peng"
    },
    {
      "name": "Zhe Wang"
    },
    {
      "name": "Hailong Liu"
    },
    {
      "name": "Zhen Zhang"
    },
    {
      "name": "Mengjie Gao"
    },
    {
      "name": "Lan Wang"
    },
    {
      "name": "Liangsheng Xu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8tyt0yahk8hzp.bib",
  "cited_by": 0,
  "doi": "10.3389/fpls.2026.1979662",
  "fulltext_url": null,
  "id": "8tyt0yahk8hzp",
  "issns": [
    "1664-462X"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fpls.2026.1979662",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "feed-journal",
      "biology/plant-biology"
    ]
  ],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-05",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/8tyt0yahk8hzp.ris",
  "sources": [
    {
      "first_seen": "2026-11-05T06:20:18Z",
      "native_id": "10.3389/fpls.2026.1979662",
      "source": "feed-frontiers",
      "url": "https://www.frontiersin.org/articles/10.3389/fpls.2026.1979662"
    },
    {
      "first_seen": "2026-11-05T12:21:12Z",
      "native_id": "10.3389/fpls.2026.1979662",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fpls.2026.1979662/full"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "feed-journal:biology/plant-biology",
      "subfield": "plant-biology"
    }
  ],
  "title": "The secreted GH43 protein VpGHa1 functions as an effector to suppress plant immunity and contributes to stress adaptation in Valsa pyri",
  "title_text": "The secreted GH43 protein VpGHa1 functions as an effector to suppress plant immunity and contributes to stress adaptation in Valsa pyri",
  "type": "peer-reviewed",
  "updated_at": "2026-11-07T00:21:17Z",
  "url": "https://research.draconitic.com/paper/8tyt0yahk8hzp",
  "venue": "Frontiers in Plant Science",
  "versions": []
}