Université Paris-Saclay, CNRS, INRAE, Université d'Evry, Institute of Plant Sciences Paris-Saclay (IPS2), Gif-sur-Yvette, France.
Université Paris Cité, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), Gif-sur-Yvette, France.
Nat Plants. 2023 Oct;9(10):1675-1687. doi: 10.1038/s41477-023-01511-z. Epub 2023 Aug 31.
Sex determination evolved to control the development of unisexual flowers. In agriculture, it conditions how plants are cultivated and bred. We investigated how female flowers develop in monoecious cucurbits. We discovered in melon, Cucumis melo, a mechanism in which ethylene produced in the carpel is perceived in the stamen primordia through spatially differentially expressed ethylene receptors. Subsequently, the CmEIN3/CmEIL1 ethylene signalling module, in stamen primordia, activates the expression of CmHB40, a transcription factor that downregulates genes required for stamen development and upregulates genes associated with organ senescence. Investigation of melon genetic biodiversity revealed a haplotype, originating in Africa, altered in EIN3/EIL1 binding to CmHB40 promoter and associated with bisexual flower development. In contrast to other bisexual mutants in cucurbits, CmHB40 mutations do not alter fruit shape. By disentangling fruit shape and sex-determination pathways, our work opens up new avenues in plant breeding.
性别决定进化以控制单性花的发育。在农业中，它决定了植物的种植和繁殖方式。我们研究了雌雄同株葫芦科植物中雌花的发育方式。我们在甜瓜（Cucumis melo）中发现了一种机制，其中在心皮中产生的乙烯通过空间差异表达的乙烯受体在雄蕊原基中被感知。随后，在雄蕊原基中，CmEIN3/CmEIL1 乙烯信号模块激活转录因子 CmHB40 的表达，该转录因子下调雄蕊发育所需的基因，并上调与器官衰老相关的基因。对甜瓜遗传多样性的研究发现了一种源自非洲的单倍型，其在 EIN3/EIL1 与 CmHB40 启动子的结合中发生改变，与两性花的发育有关。与葫芦科中的其他两性突变体不同，CmHB40 突变不会改变果实形状。通过分离果实形状和性别决定途径，我们的工作为植物育种开辟了新途径。
