The Arabidopsis SWI/SNF protein BAF60 mediates seedling growth control by modulating DNA accessibility

Teddy Jegu (1, 2, 3, 4) , Alaguraj Veluchamy (5) , Juan Sebastien Ramirez Prado (1, 2, 5) , Charley Rizzi Paillet (1, 2) , Magali Perez (1, 2) , Anaïs Lhomme (1, 2) , David Latrasse (1, 2) , Emeline Coleno (1, 2) , Serge Vicaire (6) , Stephanie Legras (6) , Bernard Jost (6) , Martin Rougée (7) , Fredy Barneche (7) , Catherine Bergounioux (1, 2) , Martin Crespi (1, 2) , Magdy M. Mahfouz (5) , Heribert Hirt (1, 2, 5) , Cécile Raynaud (1, 2) , Moussa Benhamed (1, 2)

1 IPS2 (UMR_9213 / UMR_1403) - Institut des Sciences des Plantes de Paris-Saclay
2 USPC - Université Sorbonne Paris Cité (COMUE)
3 Massachusetts General Hospital
4 Department of Genetics [Boston]
5 Division of Biological and Environmental Sciences and Engineering
6 IGBMC - Institut de Génétique et de Biologie Moléculaire et Cellulaire
7 IBENS - Institut de biologie de l'ENS Paris

Background: Plant adaptive responses to changing environments involve complex molecular interplays between intrinsic and external signals. Whilst much is known on the signaling components mediating diurnal, light, and temperature controls on plant development, their influence on chromatin-based transcriptional controls remains poorly explored. Results: In this study we show that a SWI/SNF chromatin remodeler subunit, BAF60, represses seedling growth by modulating DNA accessibility of hypocotyl cell size regulatory genes. BAF60 binds nucleosome-free regions of multiple G box-containing genes, opposing in cis the promoting effect of the photomorphogenic and thermomorphogenic regulator Phytochrome Interacting Factor 4 (PIF4) on hypocotyl elongation. Furthermore, BAF60 expression level is regulated in response to light and daily rhythms. Conclusions: These results unveil a short path between a chromatin remodeler and a signaling component to fine-tune plant morphogenesis in response to environmental conditions.

Mots clés: SWI/SNF; Chromatin; Morphogenesis; Phytochrome Interacting Factor; G-box; DNA accessibility; PIF4

Domaines: Sciences du Vivant [q-bio]; Biologie végétale

Teddy Jegu, Alaguraj Veluchamy, Juan Sebastien Ramirez Prado, Charley Rizzi Paillet, Magali Perez, et al.. The Arabidopsis SWI/SNF protein BAF60 mediates seedling growth control by modulating DNA accessibility. Genome Biology, 2017, 18, pp.114. ⟨10.1186/s13059-017-1246-7⟩. ⟨hal-02627578⟩