CCN3/NOV inhibits BMP-2-induced osteoblast differentiation by interacting with BMP and Notch signaling pathways.
We elucidate the role of CCN3/NOV, a member of the CCN family proteins, in osteoblast differentiation using MC3T3-E1 osteoblastic cells. Transduction with CCN3 adenovirus (AdCCN3) alone induced no apparent changes in the expression of osteoblast-related markers, whereas cotransduction with BMP-2 adenovirus (AdBMP-2) and AdCCN3 significantly inhibited the AdBMP-2-induced mRNA expression of Runx2, osterix, ALP, and osteocalcin. Immunoprecipitation-western analysis revealed that CCN3 associated with BMP-2. Compared to transduction with AdBMP-2 alone, cotransduction with AdBMP-2 and AdCCN3 attenuated the expression of phosphorylated Smad1/5/8 and the mRNA for Id1, Id2, and Id3. Transduction with AdCCN3 stimulated the expression of cleaved Notch1, the mRNA expression of Hes1 and Hey1/Hesr1, and the promoter activities of Hes1 and Hey1. The inhibitory effects of CCN3 on the expression of BMP-2-induced osteoblast-related markers were nullified in Hey1-deficient osteoblastic cells. These results indicate that CCN3 exerts inhibitory effects on BMP-2-induced osteoblast differentiation by its involvement of the BMP and Notch signaling pathways.
Minamizato
Tokutaro
T
Section of Oral Pathology, Graduate School of Tokyo Medical and Dental University, 1-5-45 Yushima, Tokyo 113-8549, Japan.
Sakamoto
Kei
K
Liu
Tingjiao
T
Kokubo
Hiroki
H
Katsube
Ken-ichi
K
Perbal
Bernard
B
Nakamura
Seiji
S
Yamaguchi
Akira
A
D016475:3T3 Cells; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000037:antagonists & inhibitors*; D002454:Cell Differentiation / Q000502:physiology*; D055513:Connective Tissue Growth Factor; D006801:Humans; D017874:Immediate-Early Proteins / Q000502:physiology*; D036341:Intercellular Signaling Peptides and Proteins / Q000502:physiology*; D051379:Mice; D055514:Nephroblastoma Overexpressed Protein; D010006:Osteoblasts / Q000502:physiology*; D051880:Receptors, Notch / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors*
C525718:BMP2 protein, human; C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; C526317:CCN2 protein, human; C526318:CCN2 protein, mouse; C526319:CCN3 protein, human; C526320:Ccn3 protein, mouse; D017874:Immediate-Early Proteins; D036341:Intercellular Signaling Peptides and Proteins; D055514:Nephroblastoma Overexpressed Protein; D051880:Receptors, Notch; D016212:Transforming Growth Factor beta; D055513:Connective Tissue Growth Factor