{
  "abstract": "Seed number per pod is a major soybean yield-component trait, yet experimentally validated causal modules remain poorly defined. Here, we identify and functionally validate a soybean NAT-ULT regulatory module controlling ovule and seed number per pod. Through a visual screen of a fast-neutron-irradiated Glycine max cv. Williams 82 population, we isolated MO27, which increased four-seeded pod frequency from approximately 2-4% in wild type to 27-30%, without major changes in plant architecture, total pod number, or seed morphology. Comparative genome hybridization mapped the phenotype to a 46.7-kb chromosome 2 deletion containing GmNAT1 and chromosome 6 deletions encompassing GmULT-B1 and GmULT-B3. Ovule-clearing analysis showed that increased seed number originated before fertilization through elevated formation of four-ovule ovaries. CRISPR/Cas9-mediated mutagenesis of GmNAT1, GmULT-B1, and GmULT-B3 increased four-seeded pod frequency without detectable penalties in 100-seed weight, total pod number, or plant height. Tomato SlULT triple mutants also increased floral organ and locule number, supporting conserved ULT-like function in reproductive organ patterning. RNA-seq interaction analysis revealed a chromosome 6-dominant transcriptional state, accompanied by selective non-additive reprogramming of hormone/ovule-number and cell-wall-remodeling modules. Integrated genetic and transcriptomic analyses support a hierarchical model in which NAT-ULT perturbation may enhance meristematic competence and remodel reproductive developmental programs, while additional fast-neutron-background-associated transcriptional changes may further modulate the phenotype. These findings define NAT-ULT as a molecular target for engineering soybean seed number per pod.",
  "abstract_shown": true,
  "affiliations": [
    "University of Missouri"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "C. X. Nguyen"
    },
    {
      "name": "J. H. Song"
    },
    {
      "name": "V. Kumar"
    },
    {
      "name": "M. V. Nguyen"
    },
    {
      "name": "S. Evans"
    },
    {
      "name": "S. Dai"
    },
    {
      "affs": [
        0
      ],
      "name": "M. G. Stacey"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/d1hsxhnafz961.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.09.758010",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.10.09.758010v1.full",
  "id": "d1hsxhnafz961",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.10.09.758010v1",
  "language": null,
  "licence": "CC-BY-NC",
  "licence_label": "CC BY-NC",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "plant biology"
    ],
    [
      "openalex",
      "1110|Soybean genetics and cultivation"
    ]
  ],
  "openalex": "W7221534248",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.10.09.758010v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-09",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/d1hsxhnafz961.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:22Z",
      "native_id": "10.64898/2026.10.09.758010",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.10.09.758010v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:plant biology",
      "subfield": "plant-biology"
    }
  ],
  "title": "Engineering the NAT-ULT module increases seed number per pod in soybean",
  "title_text": "Engineering the NAT-ULT module increases seed number per pod in soybean",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:22Z",
  "url": "https://research.draconitic.com/paper/d1hsxhnafz961",
  "venue": "bioRxiv",
  "versions": []
}