A G protein-coupled receptor is required in cartilaginous and dense connective tissues to maintain spine alignment
Abstract
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 (i.e., ligaments and tendons) are essential for the maintenance of spinal alignment. We show that the adhesion G protein-coupled receptor ADGRG6, previously implicated in human AIS association studies, is required in these tissues to maintain typical spine alignment in mice. Furthermore, we show that ADGRG6 regulates biomechanical properties of tendon and stimulates CREB signaling governing gene expression in cartilaginous tissues of the spine. Treatment with a cAMP agonist could mirror aspects of receptor function in culture, thus defining core pathways for regulating these axial cartilaginous and connective tissues. As ADGRG6 is a key gene involved in human AIS, these findings open up novel therapeutic opportunities for human scoliosis.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
NIH Office of the Director (R01AR072009)
- Ryan S Gray
NIH Office of the Director (R01AR071967)
- Courtney M Karner
NIH Office of the Director (R01AR076325)
- Courtney M Karner
NIH Office of the Director (F32AR073648)
- Zhaoyang Liu
Vontobel-Stiftung
- Jess G Snedeker
NIH Office of the Director (K99AR077090)
- Zhaoyang Liu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Michel Bagnat, Duke University, United States
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (AUP-2018-00276) of the University of Texas at Austin.
Version history
- Preprint posted: February 22, 2021 (view preprint)
- Received: February 23, 2021
- Accepted: July 22, 2021
- Accepted Manuscript published: July 28, 2021 (version 1)
- Version of Record published: August 2, 2021 (version 2)
- Version of Record updated: August 24, 2021 (version 3)
Copyright
© 2021, Liu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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