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Published on: October 9, 2014
Tenascin in bone morphogenesis: expression by osteoblasts and cell type-specific expression of splice variants
1Rheumatology Research Unit, Addenbrooke's Hospital, Cambridge, UK.
Journal of Cell Science
|November 1, 1992
Summary
Tenascin, an extracellular matrix glycoprotein, is produced by osteoblasts during bone development. Its expression and splice variants are specific to cell types involved in osteogenesis and chondrogenesis.
Area of Science:
- Biochemistry
- Developmental Biology
- Cell Biology
Background:
- Tenascin is an extracellular matrix glycoprotein found during osteogenesis and chondrogenesis.
- It is absent in mature bone and cartilage.
- Its role in bone development requires further investigation.
Purpose of the Study:
- To investigate the expression of tenascin by osteoblastic cells.
- To determine the specific splice variants of tenascin expressed by different cell types.
- To understand the role of tenascin during bone development.
Main Methods:
- Immunoblotting and immunocytochemistry to detect tenascin protein.
- In situ hybridization using cDNA probes to detect tenascin mRNA.
- Analysis of tenascin expression in osteoblast-like cell lines and primary cultures.
- Comparison of tenascin expression in osteogenic and chondrogenic regions of developing bone.
Main Results:
- Tenascin is secreted and deposited in the matrix by osteoblast-like cells and primary osteoblast cultures.
- Extracellular tenascin is found in cell aggregates expressing alkaline phosphatase.
- Different tenascin splice variants are synthesized by osteoblasts and fibroblasts.
- In situ hybridization revealed tenascin mRNA in osteogenic and chondrogenic regions, with specific variants in osteogenic areas.
- Tenascin mRNA and protein are codistributed in osteogenic regions, but protein persists in cartilage where mRNA is absent.
Conclusions:
- Osteoblasts synthesize tenascin.
- Tenascin expression and splice variants are cell type-specific during bone development.
- Tenascin plays a role in osteogenic and chondrogenic processes.
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