EMF2 deficiency disrupts epigenetic and chromatin organization landscapes, blocking root regeneration competence in Arabidopsis
Year: 2026
Type: article
Abstract: Plant de novo organogenesis depends on callus formation, yet the epigenetic mechanisms governing organ regeneration remain poorly understood. EMBRYONIC FLOWER 2 (EMF2), a core component of Polycomb Repressive Complex 2, mediates transcriptional repression through H3K27me3 and is essential for root regeneration in Arabidopsis. Here, we investigate how EMF2-mediated H3K27me3 shapes chromatin architecture and gene expression during root regeneration. We combined time-course transcriptome profiling, H3K27me3 chromatin immunoprecipitation, in situ Hi-C, and a probe hybridization-based Capture Hi-C approach to analyze chromatin organization and gene expression dynamics in wild-type and emf2 calli during root induction. Although emf2 calli lost root regeneration capacity, they retained responsiveness to root induction signals. Despite large-scale reduction of H3K27me3 across the emf2 genome, many genes remained transcriptionally inactive, coinciding with the formation of new long-range chromatin interactions and weakened intra- and peri-domain contacts. Genes with low basal transcription were preferentially derepressed following extensive H3K27me3 loss. Our results demonstrate that large-scale reduction of H3K27me3 in emf2 drives dynamic reorganization of chromatin architecture in Arabidopsis callus, providing new insights into how histone modification and three-dimensional chromatin topology coordinately regulate gene expression during plant regeneration.
Source: New Phytologist
DOI: 10.1111/nph.71298
Institutions: University of Hohenheim, Hebrew University of Jerusalem
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $5,790
OpenAlex ID: W7162790822