A G protein-coupled receptor is required in cartilaginous and dense connective tissues to maintain spine alignment

Summary

Adolescent idiopathic scoliosis (AIS) is the most common spine disorder affecting children worldwide, yet little is known about the pathogenesis of this disorder. Here, we demonstrate that genetic regulation of structural components of the axial skeleton, the intervertebral discs and dense connective tissues (e.g., ligaments and tendons), are essential for maintenance of spinal alignment. We show that the G-coupled protein receptor Adgrg6, previously implicated in human AIS association studies, is required in these tissues to maintain typical spine morphology. We show that Adgrg6 regulates biomechanical properties of tendon and stimulates CREB signaling governing gene expression in cartilaginous tissues of the spine. Treatment with an cAMP agonist was able to mirror aspects of receptor function in culture defining core pathways for regulation of these axial connective tissues. As ADGRG6 is a key gene involved in human AIS, these findings open up novel therapeutic opportunities for human scoliosis.