This study reports a bivalent factor, ULTRAPETALA1, that can counteract as well as promote PRC2 activity at hundreds of developmental genes in Arabidopsis thaliana. The pro-PRC2 activity of ULTRAPETAL...

Team: Environment, Metabolism, spermatogenesis, pathophysiology and inheritance Analysis of spermatogonial stem cell homeostasis and their chemoresistance.   Team: ERO: Epigenetic Regulations & Ontoge...

Silvère Baron and his team “Nurep” received the EGP Foundation Prize, under the aegis of the Fondation de France, for their research on “Nuclear Receptors and Pathophysiology” in prostate cancer. The ...

The Search Committee for Director of the GReD Institute invites expressions of interest from potential candidates for the position of Director of the Institute, starting from the 1st of January 2027 f...

Soutenez le Téléthon en faisant un don sur la page de MyoNeurALP fait son Téléthon 2024 via https://mapage.telethon.fr/animation/INMG-LIBM-GIN-iGReD

Cell fate choice and differentiation as well as the maintenance of specialized cells function require a tight and coordinated regulation of genome expression. One key layer of regulation takes place a...

Maintenance of ovarian cell identity is required throughout life to prevent the activation of the testicular programme, but the epigenetic mechanisms underlying this process remain poorly understood. Although TRIM28 is required to prevent granulosa-to-Sertoli transdifferentiation, it can act both as a regulator of H3K9me3-dependent heterochromatin and as a transcriptional co-regulator through its E3 SUMOligase activity. Here, we combined CUT&RUN, ATAC-seq and RNA-seq to define the respective contributions of these activities to maintain ovarian cell identity. Strikingly, only a small fraction of TRIM28-bound regions was associated with H3K9me3. Although Trim28 deletion induced focal H3K9me3 loss, it had limited transcriptional consequences and primarily affected repetitive elements rather than regions controlling testis-determining genes. In contrast, Trim28 loss led to reductions in chromatin accessibility and H3K27ac at regions enriched for ovarian transcription factor (TF) motifs FOXL2, NR5A2, ESR2 and RUNX1. Moreover, TRIM28 was frequently co-localised with these factors on chromatin, and the accessibility these co-bound regions were reduced by Trim28 deletion. Finally, SUMOylation loss was observed in regions co-occupied by TRIM28 and the ovarian TFs. Together, our findings identify TRIM28 as a central organiser of ovarian TF hubs whose predominant function is to preserve granulosa cell identity through stabilisation of lineage-specific TFs rather than H3K9me3-dependent heterochromatin. ### Competing Interest Statement The authors have declared no competing interest. Agence Nationale de la Recherche, https://ror.org/00rbzpz17, ANR-24-SFSC-0001, ANR-21-CE14-0061

A clinical trial, coordinated by Matthieu Jabaudon, PU-PH within the Translational Approach to Epithelial Lesions and Their Repair team, provides essential data on sedation strategies in intensive car...