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Bone morphogenetic protein-2 converts the differentiation pathway of C2C12 myoblasts into the osteoblast lineage.
- Source :
-
The Journal of cell biology [J Cell Biol] 1994 Dec; Vol. 127 (6 Pt 1), pp. 1755-66. - Publication Year :
- 1994
-
Abstract
- The implantation of bone morphogenetic protein (BMP) into muscular tissues induces ectopic bone formation at the site of implantation. To investigate the mechanism underlying this process, we examined whether recombinant bone morphogenetic protein-2 (BMP-2) converts the differentiation pathway of the clonal myoblastic cell line, C2C12, into that of osteoblast lineage. Incubating the cells with 300 ng/ml of BMP-2 for 6 d almost completely inhibited the formation of the multinucleated myotubes expressing troponin T and myosin heavy chain, and induced the appearance of numerous alkaline phosphatase (ALP)-positive cells. BMP-2 dose dependently induced ALP activity, parathyroid hormone (PTH)-dependent 3',5'-cAMP production, and osteocalcin production at concentrations above 100 ng/ml. The concentration of BMP-2 required to induce these osteoblastic phenotypes was the same as that required to almost completely inhibit myotube formation. Incubating primary muscle cells with 300 ng/ml of BMP-2 for 6 d also inhibited myotube formation, whereas induced ALP activity and osteocalcin production. Incubation with 300 ng/ml of BMP-2 suppressed the expression of mRNA for muscle creatine kinase within 6 h, whereas it induced mRNA expression for ALP, PTH/PTH-related protein (PTHrP) receptors, and osteocalcin within 24-48 h. BMP-2 completely inhibited the expression of myogenin mRNA by day 3. By day 3, BMP-2 also inhibited the expression of MyoD mRNA, but it was transiently stimulated 12 h after exposure to BMP-2. Expression of Id-1 mRNA was greatly stimulated by BMP-2. When C2C12 cells pretreated with BMP-2 for 6 d were transferred to a colony assay system in the absence of BMP-2, more than 84% of the colonies generated became troponin T-positive and ALP activity disappeared. TGF-beta 1 also inhibited myotube formation in C2C12 cells, and suppressed the expression of myogenin and MyoD mRNAs without inducing that of Id-1 mRNA. However, no osteoblastic phenotype was induced by TGF-beta 1 in C2C12 cells. TGF-beta 1 potentiated the inhibitory effect of BMP-2 on myotube formation, whereas TGF-beta 1 reduced ALP activity and osteocalcin production induced by BMP-2 in C2C12 cells. These results indicate that BMP-2 specifically converts the differentiation pathway of C2C12 myoblasts into that of osteoblast lineage cells, but that the conversion is not heritable.
- Subjects :
- Alkaline Phosphatase biosynthesis
Animals
Bone Morphogenetic Proteins
Cell Differentiation drug effects
Creatine Kinase biosynthesis
Cyclic AMP biosynthesis
DNA-Binding Proteins biosynthesis
DNA-Binding Proteins genetics
Dose-Response Relationship, Drug
Helix-Loop-Helix Motifs
Inhibitor of Differentiation Protein 1
Mice
Muscles cytology
Muscles embryology
MyoD Protein biosynthesis
MyoD Protein genetics
Myogenin biosynthesis
Myogenin genetics
Osteocalcin biosynthesis
Parathyroid Hormone biosynthesis
Phenotype
RNA, Messenger analysis
Time Factors
Transforming Growth Factor beta pharmacology
Bone Development physiology
Muscles drug effects
Osteoblasts physiology
Proteins pharmacology
Repressor Proteins
Stem Cells drug effects
Transcription Factors
Subjects
Details
- Language :
- English
- ISSN :
- 0021-9525
- Volume :
- 127
- Issue :
- 6 Pt 1
- Database :
- MEDLINE
- Journal :
- The Journal of cell biology
- Publication Type :
- Academic Journal
- Accession number :
- 7798324
- Full Text :
- https://doi.org/10.1083/jcb.127.6.1755