Maternal epigenetic pathways control parental contributions to Arabidopsis early embryogenesis.

Daphné Autran (1) , Célia Baroux (2) , Michael T Raissig (2) , Thomas Lenormand (3) , Michael Wittig (4) , Stefan Grob (2) , Andrea Steimer (2) , Matthias Barann (4) , Ulrich C Klostermeier (4) , Olivier Leblanc (1) , Jean-Philippe Vielle-Calzada (5) , Phillip Rosenstiel (4) , Daniel Grimanelli (1) , Ueli Grossniklaus (2)

1 UMR DIADE - Diversité, adaptation, développement des plantes
2 Institute of Plant Biology and Zürich-Basel Plant Science Center
3 CEFE - Centre d’Ecologie Fonctionnelle et Evolutive
4 Institute of Clinical Molecular Biology
5 LANGEBIO - National Laboratory of Genomics for Biodiversity

Defining the contributions and interactions of paternal and maternal genomes during embryo development is critical to understand the fundamental processes involved in hybrid vigor, hybrid sterility, and reproductive isolation. To determine the parental contributions and their regulation during Arabidopsis embryogenesis, we combined deep-sequencing-based RNA profiling and genetic analyses. At the 2-4 cell stage there is a strong, genome-wide dominance of maternal transcripts, although transcripts are contributed by both parental genomes. At the globular stage the relative paternal contribution is higher, largely due to a gradual activation of the paternal genome. We identified two antagonistic maternal pathways that control these parental contributions. Paternal alleles are initially downregulated by the chromatin siRNA pathway, linked to DNA and histone methylation, whereas transcriptional activation requires maternal activity of the histone chaperone complex CAF1. Our results define maternal epigenetic pathways controlling the parental contributions in plant embryos, which are distinct from those regulating genomic imprinting.

Domaines: Biologie du développement

Daphné Autran, Célia Baroux, Michael T Raissig, Thomas Lenormand, Michael Wittig, et al.. Maternal epigenetic pathways control parental contributions to Arabidopsis early embryogenesis.. Cell, 2011, 145 (5), pp.707-19. ⟨10.1016/j.cell.2011.04.014⟩. ⟨hal-00623751⟩