Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Mol Endocrinol. 2010 Mar;24(3):621-31. doi: 10.1210/me.2009-0424. Epub 2010 Feb 11.

Ligand-mediated activation of an engineered gs g protein-coupled receptor in osteoblasts increases trabecular bone formation.

Author information

  • 1Gladstone Institute of Cardiovascular Disease, 1650 Owens Street, San Francisco, California 94158, USA. ehsiao@gladstone.ucsf.edu

Abstract

Age-dependent changes in skeletal growth play important roles in regulating skeletal expansion and in the course of many diseases affecting bone. How G protein-coupled receptor (GPCR) signaling affects these changes is poorly understood. Previously, we described a mouse model expressing Rs1, an engineered receptor with constitutive G(s) activity. Rs1 expression in osteoblasts from gestation induced a dramatic age-dependent increase in trabecular bone with features resembling fibrous dysplasia; however, these changes were greatly minimized if Rs1 expression was delayed until after puberty. To further investigate whether ligand-induced activation of the G(s)-GPCR pathway affects bone formation in adult mice, we activated Rs1 in adult mice with the synthetic ligand RS67333 delivered continuously via an osmotic pump or intermittently by daily injections. We found that osteoblasts from adult animals can be stimulated to form large amounts of bone, indicating that adult mice are sensitive to the dramatic bone- forming actions of G(s) signaling in osteoblasts. In addition, our results show that intermittent and continuous activation of Rs1 led to structurally similar but quantitatively different degrees of trabecular bone formation. These results indicate that activation of a G(s)-coupled receptor in osteoblasts of adult animals by either intermittent or continuous ligand administration can increase trabecular bone formation. In addition, osteoblasts located at the bone epiphyses may be more responsive to G(s) signaling than osteoblasts at the bone diaphysis. This model provides a powerful tool for investigating the effects of ligand-activated G(s)-GPCR signaling on dynamic bone growth and remodeling.

PMID:
20150184
[PubMed - indexed for MEDLINE]
PMCID:
PMC2840804
Free PMC Article

Images from this publication.See all images (5)Free text

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Atypon Icon for PubMed Central
    Loading ...
    Write to the Help Desk