Light signaling controls nuclear architecture reorganization during seedling establishment

• DOI: 10.1073/pnas.1503512112
• Publication Date: 2015-05-12T02:43:32Z
• Authors: Clara Bourbousse; Imen Mestiri; Gerald Zabulon; Mickaël Bourge; Fabio Formiggini; Maria A. Koini; Spencer C. Brown; Paul Fransz; Chris Bowler; Fredy Barneche
• Keywords: Photomorphogenesis; Cotyledon

The spatial organization of chromatin can be subject to extensive remodeling in plant somatic cells response developmental and environmental signals. However, the mechanisms controlling these dynamic changes their functional impact on nuclear activity are poorly understood. Here, we determined that light perception triggers a switch between two different architectural schemes during Arabidopsis postembryonic development. Whereas progressive nucleus expansion heterochromatin rearrangements cotyledon achieved similarly under dark conditions germination, later steps lead mature phenotypes intimately associated with photomorphogenic transition an organ-specific manner. signaling integrators DE-ETIOLATED 1 CONSTITUTIVE PHOTOMORPHOGENIC maintain decondensed state etiolated cotyledons. In contrast, cryptochrome-mediated photoperception releases compaction within conspicuous chromocenters. For all tested loci, condensation photomorphogenesis does not detectably rely DNA methylation-based processes. Notwithstanding, efficiency transcriptional gene silencing may impacted transition, as based reactivation transposable element-driven reporter genes. Finally, report global engagement RNA polymerase II transcription is highly increased conditions, suggesting involves from globally quiescent more active states. Given findings, propose light-triggered architecture underlie interplays reorganization reprogramming establishment photosynthesis.