CCN2 Is Necessary for Adhesive Responses to Transforming Growth Factor-β1 in Embryonic Fibroblasts

Autor: Daphne Pala, Carol M. Black, David E. Carter, Lee Anne Stanton, Xu Shiwen, Richard Stratton, Sarah L. Howat, Karen M. Lyons, George Bou-Gharios, Elisabetta A. Renzoni, Frank Beier, Laura Kennedy, Yunliang Chen, David Abraham, Jeremy D. Pearson, Andrew Leask
Rok vydání: 2006
Předmět:
Time Factors
Transcription
Genetic
Blotting
Western
AKT1
Mice
Transgenic
Biology
Transfection
Biochemistry
Immediate-Early Proteins
Transforming Growth Factor beta1
Wortmannin
Focal adhesion
Mice
Phosphatidylinositol 3-Kinases
chemistry.chemical_compound
Transforming Growth Factor beta
TGF beta signaling pathway
Cell Adhesion
medicine
Animals
RNA
Messenger
Enzyme Inhibitors
Phosphorylation
Fibroblast
Molecular Biology
Protein kinase B
Oligonucleotide Array Sequence Analysis
integumentary system
Reverse Transcriptase Polymerase Chain Reaction
Connective Tissue Growth Factor
Nucleic Acid Hybridization
Cell Biology
Fibroblasts
Molecular biology
Fibronectins
Cell biology
Androstadienes
Fibronectin
medicine.anatomical_structure
chemistry
biology.protein
Intercellular Signaling Peptides and Proteins
RNA
Collagen
Proto-Oncogene Proteins c-akt
Signal Transduction
Transforming growth factor
Zdroj: Journal of Biological Chemistry. 281:10715-10726
ISSN: 0021-9258
DOI: 10.1074/jbc.m511343200
Popis: CCN2 is induced by transforming growth factor-beta (TGFbeta) in fibroblasts and is overexpressed in connective tissue disease. CCN2 has been proposed to be a downstream mediator of TGFbeta action in fibroblasts; however, the role of CCN2 in regulating this process unclear. By using embryonic fibroblasts isolated from ccn2-/- mice, we showed that CCN2 is required for a subset of responses to TGFbeta. Affymetrix genome-wide expression profiling revealed that 942 transcripts were induced by TGFbeta greater than 2-fold in ccn2+/+ fibroblasts, of which 345 were not induced in ccn2-/- fibroblasts, including pro-adhesive and matrix remodeling genes. Whereas TGFbeta properly induced a generic Smad3-responsive promoter in ccn2-/- fibroblasts, TGFbeta-induced activation of focal adhesion kinase (FAK) and Akt was reduced in ccn2-/- fibroblasts. Emphasizing the importance of FAK and Akt activation in CCN2-dependent transcriptional responses to TGFbeta in fibroblasts, CCN2-dependent transcripts were not induced by TGFbeta in fak-/- fibroblasts and were reduced by wortmannin in wild-type fibroblasts. Akt1 overexpression in ccn2-/- fibroblasts rescued the TGFbeta-induced transcription of CCN2-dependent mRNA. Finally, induction of TGFbeta-induced fibroblast adhesion to fibronectin and type I collagen was significantly diminished in ccn2-/- fibroblasts. Thus in embryonic fibroblasts, CCN2 is a necessary cofactor required for TGFbeta to activate the adhesive FAK/Akt/phosphatidylinositol 3-kinase cascade, FAK/Akt-dependent genes, and adhesion to matrix.
Databáze: OpenAIRE
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