Osteonectin is a minor component of mineralized connective tissues in rat
- 1 April 1986
- journal article
- research article
- Published by Canadian Science Publishing in Biochemistry and Cell Biology
- Vol. 64 (4), 356-362
- https://doi.org/10.1139/o86-049
Abstract
Osteonectin is a major glycoprotein of porcine and bovine bones and teeth that is found associated with hydroxylapatite crystal surfaces. From the ability of osteonectin to bind calcium ions, it has been proposed as a possible nucleator of hydroxylapatite crystal formation. Analysis of hydroxylapatite-bound proteins of rat bone and dentine, however, has revealed that osteonectin represents only 2.5 ± 1.5% of the hydroxylapatite-bound protein in long bones, 0.9 ± 0.5% in calvariae, and < 0.1% in incisor dentine of animals of different ages. Further, in vivo pulse–chase studies carried out in young adult rats have shown osteonectin to be synthesized at low levels in these tissues. Similarly, low levels of osteonectin were synthesized by rat calvarial cells in vitro. In contrast, fibroblastic cells from periodontal ligament and gingiva synthesized significantly greater amounts of osteonectin. These studies indicate that the low quantities of osteonectin in rat mineralized tissues are a consequence of low rates of formation rather than being due to rapid turnover. The virtual absence of osteonectin in incisor dentine correlates with the lack of peritubular dentine in rat, whereas the low osteonectin content of rat bones may reflect differences in their structure and biophysical properties compared with bones of larger mammals.Keywords
This publication has 15 references indexed in Scilit:
- An osteonectinlike protein in porcine periodontal ligament and its synthesis by periodontal ligament fibroblastsCanadian Journal of Biochemistry and Cell Biology, 1984
- Osteonectin, bone proteoglycan, and phosphophoryn defects in a form of bovine osteogenesis imperfecta.Proceedings of the National Academy of Sciences, 1984
- Matrix sialoprotein of developing bone.Journal of Biological Chemistry, 1983
- Independent expression of type i collagen and fibronectin by normal fibroblast-like cellsJournal of Cell Science, 1983
- Staining of the Ca2+-binding proteins, calsequestrin, calmodulin, troponin C, and S-100, with the cationic carbocyanine dye “Stains-all”.Journal of Biological Chemistry, 1983
- Noncollagenous proteins of rat compact bone.Journal of Biological Chemistry, 1983
- Isolation of bone cell clones with differences in growth, hormone responses, and extracellular matrix production.The Journal of cell biology, 1982
- Mineral and collagen-binding proteins of fetal calf bone.Journal of Biological Chemistry, 1981
- Osteonectin, a bone-specific protein linking mineral to collagenCell, 1981
- Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications.Proceedings of the National Academy of Sciences, 1979