The developing mouse coronal suture at single-cell resolution

Sutures separate the flat bones of the skull and enable coordinated growth of the brain and overlying cranium. In order to uncover the cellular diversity within sutures, we conducted single-cell transcriptomic and histological analyses of the embryonic murine coronal suture. We identify Erg and Pthlh as early markers of osteogenic progenitors in sutures, and distinct pre-osteoblast signatures between the bone fronts and periosteum. diverse mesenchymal layers at the coronal suture, including multiple distinct meningeal layers below the suture, and ligamentous, ectocranial, and hypodermal layers above the sutureIn the ectocranial layers above the suture, we observe a ligament-like population spanning the frontal and parietal bones and expressing genes implicated in mechanosensation. Mesenchyme in and around the coronal suture is asymmetrically distributed between the frontal and parietal bones, and we identify different states of osteogenic cells extending from the bone fronts into the more mature bone, and a potential signature for sutural stem cellsIn the meningeal layers, we detect a potential chondrogenic periosteal dura population that may be involved in endochondral ossification that closes sutures. Expression of genes mutated in craniosynostosis is spread across diverse cell types, suggesting multiple points at which homeostasis can fail. This single-cell atlas provides a resource to understand the development of the coronal suture, the suture most commonly fused in craniosynostosis. Overall design: Single cell analysis of mouse embryonic coronal sutures at E15.5 and E17.5 *********************************************************************** Raw data not provided for sample GSM4983998. ***********************************************************************