About This Project

The ability of vertebrates to move and breathe depends on precise coordination between skeletal elements that arise from different embryonic tissues. We are investigating how cells that form the ribs and sternum communicate to connect properly. We hypothesize that specific signaling and adhesion genes mediate this cross-tissue interaction. Using Visium spatial transcriptomics, we will map gene activity at the rib–sternum junction to reveal how communication across this boundary evolved.

Ask the Scientists

What is the context of this research?

From salamanders to birds, mammals, and humans, the diversity of vertebrate movement and breathing depends on coordination between skeletal elements that arise from different embryonic tissues. This integration begins at the lateral somitic frontier, where cells from the backbone and body wall meet. We are investigating what kinds of communication occur at this boundary to allow the ribs and sternum to connect and form a functional articulated skeleton. We hypothesize that signaling and adhesion genes are expressed at sites of contact to enable cross-tissue integration, and that variation in these mechanisms underlies evolutionary differences in locomotion and respiration. Using Visium spatial transcriptomics, we will map gene expression across developmental stages to identify the molecular interactions that coordinate rib–sternum attachment and model how this communication evolved.

What is the significance of this project?

As vertebrate embryos develop, their bodies are built by two major tissues: the somitic mesoderm, which forms the ribs and back muscles, and the lateral plate mesoderm, which gives rise to the limbs, sternum, and body wall. Where these domains meet at the lateral somitic frontier, a precise dialogue ensures that ribs attach properly to the sternum. How this communication is achieved at the molecular level remains unknown. Morphological variation in the integration of the axial and appendicular systems has driven the evolution of diverse modes of locomotion and respiration in tetrapods. Our project seeks to reveal the gene networks defining the lateral somitic frontier at the rib–sternum junction, uncovering the molecular language that knits the body together. This work will illuminate how evolution reuses developmental programs to build new structures and may inform understanding and treatment of congenital defects affecting the chest wall and diaphragm.

What are the goals of the project?

We will perform Visium spatial transcriptomic analysis on mouse embryos from embryonic days 11–14, a critical window that spans early rib and sternum formation through midline fusion. Embryos carrying lineage reporters marking somitic (muscle and rib) and lateral plate (sternum) tissues will be collected for analysis. Using the 10x Genomics Visium platform, we will map RNA expression in sections containing the rib–sternum interface to capture spatial patterns of gene activity. By comparing expression profiles across developmental stages, we will identify genes differentially expressed at the points of contact between ribs and sternum, reconstructing the molecular sequence leading to their fusion. This approach will also uncover candidate signaling and adhesion molecules that mediate cross-tissue communication at the lateral somitic frontier.