Conserved regulatory motifs in osteogenic gene promoters integrate cooperative effects of canonical Wnt and BMP pathways.
Osteoblast differentiation depends on the coordinated network of evolutionary conserved transcription factors during bone formation and homeostasis. Evidence indicates that bone morphogenetic protein (BMP) and Wnt proteins regulate several steps of skeletal development. Here, we provide a molecular description of the cooperative effects of BMP and Wnt canonical pathway on the expression of the early osteogenic genes Dlx5, Msx2, and Runx2 in C2C12 cells, primary cultures of bone marrow-mesenchymal stem cells, and organotypic calvarial cultures. Coordinated regulation of these genes leads to the cooperative activation of their downstream osteogenic target gene osterix. Induction of these genes is mediated through enhancer regions with an evolutionary conserved structure encompassing both Smad and TCF/LEF1 DNA-binding sites. Formation of a cooperative complex is mediated through DNA binding of Smads and TCF4/β-catenin to their cognate sequences, as well as protein-protein interactions between them. The formation of these cooperative transcriptional complexes results in a more efficient recruitment of coactivators such as p300. We propose that evolutionary conserved regulatory regions in specific osteogenic master genes are key integrative modules during osteogenesis.
Rodríguez-Carballo
Edgardo
E
Departament de Ciències Fisiològiques II, Universitat de Barcelona, IDIBELL, L'Hospitalet de Llobregat, Spain.
Ulsamer
Arnau
A
Susperregui
Antonio R G
AR
Manzanares-Céspedes
Cristina
C
Sánchez-García
Eva
E
Bartrons
Ramon
R
Rosa
José Luis
JL
Ventura
Francesc
F
D000818:Animals; D000831:Animals, Newborn; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D017124:Conserved Sequence / Q000502:physiology*; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004742:Enhancer Elements, Genetic / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D005786:Gene Expression Regulation / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D009154:Mutation / Q000502:physiology; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism; D010012:Osteogenesis / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000502:physiology*; D011485:Protein Binding / Q000502:physiology; D054730:Protein Interaction Domains and Motifs / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*; D012886:Skull / Q000187:drug effects / Q000378:metabolism; D051785:Smad Proteins / Q000235:genetics / Q000378:metabolism; D000076182:Sp7 Transcription Factor; D051820:TCF Transcription Factors / Q000235:genetics / Q000378:metabolism; D000073940:Transcription Factor 4; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D051153:Wnt Proteins / Q000494:pharmacology*; D060508:Wnt3 Protein; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism
D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; C495267:CTNNB1 protein, mouse; D050659:Core Binding Factor Alpha 1 Subunit; C501120:Dlx5 protein, mouse; D018398:Homeodomain Proteins; C084119:MSX2 protein; C493716:Runx2 protein, mouse; D051785:Smad Proteins; D000076182:Sp7 Transcription Factor; C479466:Sp7 protein, mouse; D051820:TCF Transcription Factors; C090743:Tcf4 protein, mouse; D000073940:Transcription Factor 4; D014157:Transcription Factors; D051153:Wnt Proteins; D060508:Wnt3 Protein; D051176:beta Catenin; D004247:DNA