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The clock genes Period 2 and Cryptochrome 2 differentially balance bone formation
Erik Maronde1, Arndt F Schilling, Sebastian Seitz
1Dr. Senckenbergische Anatomie, Institute for Anatomy III, Goethe University, Frankfurt, Germany. E.Maronde@em.uni-frankfurt.de
Plos One
|July 17, 2010
Summary
Circadian clock genes Per2 and Cry2 influence bone volume by regulating osteoblasts and osteoclasts, respectively. Their distinct roles highlight complex mechanisms in bone remodeling.
Area of Science:
- Chronobiology
- Skeletal Biology
- Molecular Genetics
Background:
- Circadian clock genes regulate mammalian physiological processes, including bone formation.
- Bone remodeling involves osteoblasts (bone formation) and osteoclasts (bone resorption).
Purpose of the Study:
- To investigate the role of clock genes, specifically Per2 and Cry2, in regulating bone volume.
- To determine the cellular mechanisms by which these clock genes affect bone homeostasis.
Main Methods:
- Analysis of bone volume phenotype in mice with mutations in clock genes (Per2 and Cry2).
- Assessment of osteoblast and osteoclast specific parameters in mutant mice.
Main Results:
- Mice lacking Per2 or Cry2 exhibited significantly increased bone volume at 12 weeks.
- Per2 mutations affected osteoblast parameters, while Cry2 mutations impacted osteoclast parameters.
- Simultaneous inactivation of Per2 and Cry2 restored normal bone volume, with Cry2's effect on osteoclasts persisting.
Conclusions:
- Cry2 and Per2 regulate bone volume through distinct pathways.
- Cry2 primarily influences the osteoclastic component of bone remodeling.
- Per2 primarily acts on osteoblast parameters involved in bone formation.
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