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S100A1 and S100B are dispensable for endochondral ossification during skeletal development
Yoshifumi Mori1, Daisuke Mori, Ung-Il Chung
1Sensory & Motor System Medicine, Faculty of Medicine, University of Tokyo.
Biomedical Research (Tokyo, Japan)
|August 26, 2014
Summary
S100A1 and S100B proteins are not essential for skeletal development in mice. Their absence is compensated by other S100 proteins, indicating a redundant role in endochondral ossification.
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- S100A1 and S100B are induced by SOX transcription factors in chondrocytes.
- These proteins are known to inhibit chondrocyte hypertrophic differentiation in vitro.
- The in vivo roles of S100A1 and S100B in skeletal development remain unclear.
Purpose of the Study:
- To investigate the functional significance of S100A1 and S100B in skeletal development in vivo.
- To determine if S100A1 and S100B play essential roles in endochondral ossification.
Main Methods:
- Generation and analysis of S100a1/S100b double knockout mice.
- Assessment of skeletal growth from embryonic stage to adulthood.
- Analysis of S100 gene expression in primary chondrocytes and in vitro differentiation assays.
Main Results:
- S100a1/S100b double mutant mice exhibit normal skeletal development and growth.
- No compensatory upregulation of other S100 family members was observed in the double mutants.
- Overexpression of related S100 proteins (S100a2, S100a4, S100a10, S100a11) suppressed chondrocyte hypertrophy in vitro.
Conclusions:
- S100A1 and S100B are dispensable for endochondral ossification during skeletal development.
- The functions of S100A1 and S100B in skeletal development may be redundant due to similar functions of other S100 proteins.
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