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bioRxiv · 10.1101/2024.09.18.613646

Genomic imprinting in an early-diverging angiosperm reveals ancient mechanisms for seed initiation in flowering plants

Florez-Rueda, A. M.·Scharmann, M.·de Souza, L. P.·Fernie, A. R.·Bachelier, J. B.·Figueiredo, D. D.
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Abstract

The evolution of the seed habit marks a pivotal innovation of the spermatophytes. Angiosperms further refined this trait by coupling the development of seed accessory structures to fertilization, optimizing resource allocation. Here, we demonstrate that post-fertilization auxin production is an evolutionarily conserved mechanism for seed initiation in angiosperms. We also provide evidence that this pathway likely emerged from a switch from maternal to paternal control after the divergence of angiosperms from their gymnosperm ancestors. Our study thus brings new insights into the evolutionary origins of the endosperm, which was a determining feature for the rapid rise to dominance of flowering plants.

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Florez-Rueda, A. M., Scharmann, M., de Souza, L. P., Fernie, A. R., Bachelier, J. B., Figueiredo, D. D.. 2024-09-19. Genomic imprinting in an early-diverging angiosperm reveals ancient mechanisms for seed initiation in flowering plants. https://doi.org/10.1101/2024.09.18.613646

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