SMAD3 and SP1/SP3 Transcription Factors Collaborate to Regulate Connective Tissue Growth Factor Gene Expression in Myoblasts in Response to Transforming Growth Factor β.
Fibrotic disorders are characterized by an increase in extracellular matrix protein expression and deposition, Duchene Muscular Dystrophy being one of them. Among the factors that induce fibrosis are Transforming Growth Factor type β (TGF-β) and the matricellular protein Connective Tissue Growth Factor (CTGF/CCN2), the latter being a target of the TGF-β/SMAD signaling pathway and is the responsible for the profibrotic effects of TGF-β. Both CTGF and TGF are increased in tissues affected by fibrosis but little is known about the regulation of the expression of CTGF mediated by TGF-β in muscle cells. By using luciferase reporter assays, site directed mutagenesis and specific inhibitors in C2C12 cells; we described a novel SMAD Binding Element (SBE) located in the 5' UTR region of the CTGF gene important for the TGF-β-mediated expression of CTGF in myoblasts. In addition, our results suggest that additional transcription factor binding sites (TFBS) present in the 5' UTR of the CTGF gene are important for this expression and that SP1/SP3 factors are involved in TGF-β-mediated CTGF expression.
Laboratorio de Diferenciación Celular y Patología, Centro de Regulación Celular y Patología (CRCP), Departamento de Biología Celular y Molecular, Pontificia Universidad Católica de Chile, Santiago, Chile.|Unité de Technologie Chimique et Biologique pour la Santé, CNRS, UMR8258, Paris, F-75006, France.|INSERM U1022, Université Paris Descartes, ENSCP Chimie-ParisTech, Paris, France.
Gonzalo
G
Córdova
Unité de Technologie Chimique et Biologique pour la Santé, CNRS, UMR8258, Paris, F-75006, France.|INSERM U1022, Université Paris Descartes, ENSCP Chimie-ParisTech, Paris, France.
Alice
A
Rochard
Laboratorio de Diferenciación Celular y Patología, Centro de Regulación Celular y Patología (CRCP), Departamento de Biología Celular y Molecular, Pontificia Universidad Católica de Chile, Santiago, Chile.
Camilo
C
Riquelme-Guzmán
Laboratorio de Diferenciación Celular y Patología, Centro de Regulación Celular y Patología (CRCP), Departamento de Biología Celular y Molecular, Pontificia Universidad Católica de Chile, Santiago, Chile.
Catalina
C
Cofré
Unité de Technologie Chimique et Biologique pour la Santé, CNRS, UMR8258, Paris, F-75006, France.|INSERM U1022, Université Paris Descartes, ENSCP Chimie-ParisTech, Paris, France.
Daniel
D
Scherman
Unité de Technologie Chimique et Biologique pour la Santé, CNRS, UMR8258, Paris, F-75006, France.|INSERM U1022, Université Paris Descartes, ENSCP Chimie-ParisTech, Paris, France.
Pascal
P
Bigey
Laboratorio de Diferenciación Celular y Patología, Centro de Regulación Celular y Patología (CRCP), Departamento de Biología Celular y Molecular, Pontificia Universidad Católica de Chile, Santiago, Chile.
Enrique
E
Brandan
D020121:5' Untranslated Regions; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D055513:Connective Tissue Growth Factor / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D005786:Gene Expression Regulation; D051379:Mice; D016297:Mutagenesis, Site-Directed; D032446:Myoblasts / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects; D051900:Smad3 Protein / Q000378:metabolism; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D051705:Sp3 Transcription Factor / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D020121:5' Untranslated Regions; C526318:CCN2 protein, mouse; D051900:Smad3 Protein; C497791:Smad3 protein, mouse; D016329:Sp1 Transcription Factor; C497122:Sp3 protein, mouse; D016212:Transforming Growth Factor beta; D055513:Connective Tissue Growth Factor; D051705:Sp3 Transcription Factor
CTGF/CCN2; DUCHENNE MUSCULAR DYSTROPHY; FIBROSIS; SKELETAL MUSCLE; SMAD; TGF-BETA