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Analysis of Minerals Produced by hFOB 1.19 and Saos-2 Cells Using Transmission Electron Microscopy with Energy Dispersive X-ray Microanalysis
Published on: June 24, 2018
Bone mineralization proceeds through intracellular calcium phosphate loaded vesicles: a cryo-electron microscopy
Julia Mahamid1, Amnon Sharir, Dvir Gur
1Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel. mahamid@biochem.mpg.de
Journal of Structural Biology
|March 29, 2011
Summary
Osteoblasts concentrate disordered calcium phosphate mineral granules within vesicles for bone mineralization. This intracellular mechanism is crucial for forming bone tissue in vertebrates.
Area of Science:
- Biomineralization research
- Cellular biology
- Skeletal tissue development
Background:
- Bone formation involves osteoblasts and calcium phosphate minerals like hydroxyapatite.
- Mechanisms of mineral formation, transport, and deposition in bone remain unclear.
Purpose of the Study:
- To investigate the in vivo mechanism of bone mineralization.
- To identify the role of osteoblasts and intracellular processes in mineral formation.
Main Methods:
- Cryo-electron microscopy on native frozen-hydrated developing mouse calvaria and long bones.
- Elemental analysis and electron diffraction of intracellular mineral granules.
Main Results:
- Bone-lining cells concentrate membrane-bound mineral granules within intracellular vesicles.
- Intracellular granules contain disordered calcium phosphate, a metastable precursor.
- Intracellular mineral shows lower calcium content, suggesting a cellular control mechanism.
Conclusions:
- Osteoblasts actively produce disordered mineral packets within intracellular vesicles for bone mineralization.
- This intracellular precursor strategy is conserved across various animal phyla, including vertebrates.
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