In a new mouse study, scientists at the Icahn School of Medicine at Mount Sinai demonstrate how the activity of one gene, turned on in a newly discovered group of bone-bordering cells, may play an important role in shaping the skull.
The findings are published in the journal Nature Communications in a paper titled, “Single-cell analysis identifies a key role for Hhip in murine coronal suture development,” and led by Greg Holmes, PhD, assistant professor of genetics and genomic sciences at Icahn Mount Sinai.
“Craniofacial development depends on formation and maintenance of sutures between bones of the skull,” the researchers wrote. “In sutures, growth occurs at osteogenic fronts along the edge of each bone, and suture mesenchyme separates adjacent bones. Here, we perform single-cell RNA-seq analysis of the embryonic, wild type murine coronal suture to define its population structure.”
Researchers focused on the cells of the coronal suture, a fibrous joint that connects the front and middle bone plates.
The Holmes lab worked with researchers in the labs of Bin Zhang, PhD, Harm van Bakel, PhD, and Ethylin Wang Jabs, MD, of Icahn Mount Sinai. Together they studied how the genetic activity in the cells of the coronal suture changes during early development.
Their findings suggested that a gene encoding a molecule called hedgehog interacting protein (HHIP) plays a unique role in coronal suture development. The researchers observed the gene was more active in a novel group of mesenchyme cells than it was in osteoblasts.
“Using single-cell with bulk RNA-seq analysis we have better defined the distinctive composition of the coronal suture at the transcriptional and cell population levels,” the researchers wrote.
Looking toward the future, the researchers hope that advanced single-cell genetic studies like this one will pave the way for a more thorough understanding of how a skull is shaped under healthy and disease conditions.
“Our transcriptomic approach greatly expands opportunities for hypothesis-driven research in coronal and other suture development,” concluded the researchers.