Tags

Type your tag names separated by a space and hit enter

Temporal changes in matrix protein synthesis and mRNA expression during mineralized tissue formation by adult rat bone marrow cells in culture.
J Bone Miner Res 1994; 9(2):231-40JB

Abstract

To characterize the bone-like tissue produced by rat bone marrow cells (RBMC) from young adult femurs, the synthesis of bone proteins and the expression of their mRNA were studied in vitro. RBMC plated at a density of 5 x 10(3) cells/cm2 and grown in the presence of 10(-8) M dexamethasone (Dex) and 10 mM beta-glycerophosphate (beta-GP) produced mineralized bone nodules, which were first evident at day 3 and increased markedly to day 13. However, in the absence of dexamethasone, few mineralized nodules were observed. The formation of mineralized nodules was reflected by the uptake of 45Ca, which also increased markedly to day 13. Analysis of bone protein expression by Northern and slot-blot hybridizations revealed an increase in mRNA levels of collagen type I (Col I), osteonectin/SPARC (ON), alkaline phosphatase (ALP), osteopontin (OPN), bone sialoprotein (BSP), and osteocalcin (OC) during the formation of mineralized nodules. Whereas the Col I, ON, ALP, and OPN mRNAs were expressed before the formation of mineralized nodules was evident and were also expressed at various levels in the absence of Dex, the expression of BSP and OC mRNA was induced in the bone-forming cultures. The expression of BSP mRNA was correlated temporally with bone tissue formation, reaching maximal levels on day 16. In contrast, OC mRNA was expressed later and, following induction, increased over the 28 day culture period. Production of matrix proteins during the rapid formation of the bone tissue appeared to reflect the levels of the respective mRNAs. However, whereas some of the collagen and almost all of the SPARC were secreted into the culture medium, virtually all of the OPN and most of the BSP were extracted from the mineralized tissue matrix with EDTA. Some OPN and BSP were present in the medium, especially early in the culture, and a significant amount of BSP was also found associated with the collagenous tissue matrix. These studies point to the importance of Col I, ALP, OPN, and BSP, but not ON or OC, in the initial formation of bone tissue.

Authors+Show Affiliations

Medical Research Council Group in Periodontal Physiology, University of Toronto, Ontario, Canada.No affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

8140936

Citation

Yao, K L., et al. "Temporal Changes in Matrix Protein Synthesis and mRNA Expression During Mineralized Tissue Formation By Adult Rat Bone Marrow Cells in Culture." Journal of Bone and Mineral Research : the Official Journal of the American Society for Bone and Mineral Research, vol. 9, no. 2, 1994, pp. 231-40.
Yao KL, Todescan R, Sodek J. Temporal changes in matrix protein synthesis and mRNA expression during mineralized tissue formation by adult rat bone marrow cells in culture. J Bone Miner Res. 1994;9(2):231-40.
Yao, K. L., Todescan, R., & Sodek, J. (1994). Temporal changes in matrix protein synthesis and mRNA expression during mineralized tissue formation by adult rat bone marrow cells in culture. Journal of Bone and Mineral Research : the Official Journal of the American Society for Bone and Mineral Research, 9(2), pp. 231-40.
Yao KL, Todescan R, Sodek J. Temporal Changes in Matrix Protein Synthesis and mRNA Expression During Mineralized Tissue Formation By Adult Rat Bone Marrow Cells in Culture. J Bone Miner Res. 1994;9(2):231-40. PubMed PMID: 8140936.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Temporal changes in matrix protein synthesis and mRNA expression during mineralized tissue formation by adult rat bone marrow cells in culture. AU - Yao,K L, AU - Todescan,R,Jr AU - Sodek,J, PY - 1994/2/1/pubmed PY - 2001/3/28/medline PY - 1994/2/1/entrez SP - 231 EP - 40 JF - Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research JO - J. Bone Miner. Res. VL - 9 IS - 2 N2 - To characterize the bone-like tissue produced by rat bone marrow cells (RBMC) from young adult femurs, the synthesis of bone proteins and the expression of their mRNA were studied in vitro. RBMC plated at a density of 5 x 10(3) cells/cm2 and grown in the presence of 10(-8) M dexamethasone (Dex) and 10 mM beta-glycerophosphate (beta-GP) produced mineralized bone nodules, which were first evident at day 3 and increased markedly to day 13. However, in the absence of dexamethasone, few mineralized nodules were observed. The formation of mineralized nodules was reflected by the uptake of 45Ca, which also increased markedly to day 13. Analysis of bone protein expression by Northern and slot-blot hybridizations revealed an increase in mRNA levels of collagen type I (Col I), osteonectin/SPARC (ON), alkaline phosphatase (ALP), osteopontin (OPN), bone sialoprotein (BSP), and osteocalcin (OC) during the formation of mineralized nodules. Whereas the Col I, ON, ALP, and OPN mRNAs were expressed before the formation of mineralized nodules was evident and were also expressed at various levels in the absence of Dex, the expression of BSP and OC mRNA was induced in the bone-forming cultures. The expression of BSP mRNA was correlated temporally with bone tissue formation, reaching maximal levels on day 16. In contrast, OC mRNA was expressed later and, following induction, increased over the 28 day culture period. Production of matrix proteins during the rapid formation of the bone tissue appeared to reflect the levels of the respective mRNAs. However, whereas some of the collagen and almost all of the SPARC were secreted into the culture medium, virtually all of the OPN and most of the BSP were extracted from the mineralized tissue matrix with EDTA. Some OPN and BSP were present in the medium, especially early in the culture, and a significant amount of BSP was also found associated with the collagenous tissue matrix. These studies point to the importance of Col I, ALP, OPN, and BSP, but not ON or OC, in the initial formation of bone tissue. SN - 0884-0431 UR - https://www.unboundmedicine.com/medline/citation/8140936/Temporal_changes_in_matrix_protein_synthesis_and_mRNA_expression_during_mineralized_tissue_formation_by_adult_rat_bone_marrow_cells_in_culture_ L2 - https://doi.org/10.1002/jbmr.5650090212 DB - PRIME DP - Unbound Medicine ER -