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08:42
Skeletal Phenotype Analysis of a Conditional Stat3 Deletion Mouse Model
Published on: July 3, 2020
Kindlin-3-mediated signaling from multiple integrin classes is required for osteoclast-mediated bone resorption
Sarah Schmidt1, Inaam Nakchbandi, Raphael Ruppert
1Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany.
The Journal of Cell Biology
|March 2, 2011
Summary
Kindlin-3 protein deficiency causes severe osteopetrosis by impairing osteoclast function and bone resorption. This research reveals kindlin-3
Area of Science:
- Integrative biology
- Cell biology
- Skeletal biology
Background:
- Kindlin-3 protein activates leukocyte and platelet integrins.
- Mutations in KINDLIN-3 cause immunodeficiency, bleeding, and sometimes osteopetrosis.
- The mechanism linking kindlin-3 to bone turnover remains unclear.
Purpose of the Study:
- To investigate the role of kindlin-3 in osteoclast function and bone homeostasis.
- To elucidate the mechanism behind osteopetrosis in kindlin-3 deficiency.
Main Methods:
- Analysis of kindlin-3-deficient mice.
- Assessment of osteoclast adhesion, spreading, and podosome formation.
- Genetic ablation of integrin classes in osteoclasts.
Main Results:
- Kindlin-3 deficiency leads to severe osteopetrosis in mice.
- Loss of kindlin-3 impairs osteoclast activation of β1, β2, and β3 integrins.
- Osteoclast podosome formation and bone resorption are abrogated in kindlin-3 deficient mice.
- Genetic ablation of all integrins mimics kindlin-3 deficiency, while single integrin loss impairs resorptive activity.
Conclusions:
- Kindlin-3 is essential for osteoclast function and bone resorption.
- Osteoclasts require kindlin-3 to regulate their entire integrin repertoire for bone homeostasis.
- Kindlin-3 deficiency disrupts skeletal integrity through impaired osteoclast activity.
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