Auxin response factor 10 insensitive to miR160regulation induces apospory-like phenotypes in Arabidopsis
The <i>Arabidopsis</i> megaspore mother cell (MMC) arises from somatic cells in the ovule primordium and enters meiosis to generate four megaspores. Only the most chalazal (functional megaspore, FM) survives, undergoing a series of mitoses to form the female gametophyte. We show that this commitment to the sexual germline requires spatial regulation of <i>A</i> <i>UXIN</i> <i>R</i> <i>ESPONSE</i> <i>F</i> <i>ACTOR</i> <i>10</i> (<i>ARF10</i>). <i>GFP</i>-fusion lines reveal <i>ARF10</i> expression to be restricted to cells surrounding the MMC in wild type, but ectopically disseminated throughout the ovule in transgenic mARF10 lines insensitive to miR160, an ARF10 downregulator. Significantly, mARF10 ovules develop multiple FMs with differing ploidies, forming putative supernumerary gametophytes with altered polarity and cell identities - features of aposporous apomixis. Furthermore, we confirm the complexity of ovular <i>ARF10</i> expression, being mediated by SEEDSTICK, ARGONAUTE1, and miR160. This work adds to our understanding of molecular switches possibly regulating aposporous apomixis, and may contribute the development of innovative plant breeding strategies.
Authors
- Elena Costantini (ORCID: https://orcid.org/0000-0002-5452-7647)
- Giada Callizaya Terceros (ORCID: https://orcid.org/0000-0002-4418-9840)
- Maurizio Di Marzo (ORCID: https://orcid.org/0000-0001-9045-8370)
- Rosanna Petrella (ORCID: https://orcid.org/0000-0002-2369-6632)
- Emidio Albertini (ORCID: https://orcid.org/0000-0003-2585-5649)
- Mara Cucinotta (ORCID: https://orcid.org/0000-0002-5410-9912)
- Gianpiero Marconi (ORCID: https://orcid.org/0000-0003-2669-0399)
- Silvina C. Pessino (ORCID: https://orcid.org/0000-0002-0200-8706)
- Chiara Mizzotti (ORCID: https://orcid.org/0000-0003-3644-2890)
- Davide Perrone (ORCID: https://orcid.org/0000-0002-3270-9482)
- Lucia Colombo (ORCID: https://orcid.org/0000-0001-8415-1399)
- Carolina Colono (ORCID: https://orcid.org/0000-0001-7771-2127)
- Maricel Podio (ORCID: https://orcid.org/0000-0001-9797-1089)
- Marta Adelina Mendes (ORCID: https://orcid.org/0000-0001-9223-4119)
- Celeste Azzaro
- Hugh Dickinson
Institutions
- University of Milan (IT)
- University of Perugia (IT)
- University of Oxford (GB)
- National University of Rosario (AR)
- Instituto de Investigaciones en Ciencias Agrarias de Rosario (AR)
Publication Details
- Journal
- iScience
- Published
- 2024-10-09
- DOI
- https://doi.org/10.1016/j.isci.2024.111115
- Citations
- 3
- Primary Topic
- Plant Molecular Biology Research
- Type
- article
- Field-Weighted Citation Impact
- 1.80
Funders
- Universidad Nacional de Rosario
- Università degli Studi di Milano
- European Commission
- Consejo Nacional de Investigaciones Científicas y Técnicas
- Ministero degli Affari Esteri e della Cooperazione Internazionale
- H2020 Marie Skłodowska-Curie Actions