Tensile strain increases expression of CCN2 and COL2A1 by activating TGF-β-Smad2/3 pathway in chondrocytic cells
Related Experiment Video
Updated: May 11, 2026

Generation of Induced Pluripotent Stem Cell-Derived iTenocytes via Combined Scleraxis Overexpression and 2D Uniaxial Tension
Published on: March 1, 2024
Takayuki Furumatsu1, Emi Matsumoto, Tomoko Kanazawa
1Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8558, Japan. matino@md.okayama-u.ac.jp
Abstract:
Physiologic mechanical stress stimulates expression of chondrogenic genes, such as multifunctional growth factor CYR61/CTGF/NOV (CCN) 2 and α1(II) collagen (COL2A1), and maintains cartilage homeostasis. In our previous studies, cyclic tensile strain (CTS) induces nuclear translocation of transforming growth factor (TGF)-β receptor-regulated Smad2/3 and the master chondrogenic transcription factor Sry-type HMG box (SOX) 9. However, the precise mechanism of stretch-mediated Smad activation remains unclear in transcriptional regulation of CCN2 and COL2A1. Here we hypothesized that CTS may induce TGF-β1 release and stimulate Smad-dependent chondrogenic gene expression in human chondrocytic SW1353 cells. Uni-axial CTS (0.5Hz, 5% strain) stimulated gene expression of CCN2 and COL2A1 in SW1353 cells, and induced TGF-β1 secretion. CCN2 synthesis and nuclear translocalization of Smad2/3 and SOX9 were stimulated by CTS. In addition, CTS increased the complex formation between phosphorylated Smad2/3 and SOX9. The CCN2 promoter activity was cooperatively enhanced by CTS and Smad3 in luciferase reporter assay. Chromatin immunoprecipitation revealed that CTS increased Smad2/3 interaction with the CCN2 promoter and the COL2A1 enhancer. Our results suggest that CTS epigenetically stimulates CCN2 transcription via TGF-β1 release associated with Smad2/3 activation and enhances COL2A1 expression through the complex formation between SOX9 and Smad2/3.
Related Concept Videos
TGF - β Signaling Pathway
Cell-matrix's Response to Mechanical Forces
Anchoring junctions mechanically attach a cell to the...
Canonical Wnt Signaling Pathway
Growth of Cartilage and Bone Tissue
Tension Response at Adherens Junctions
α-Catenin as a Mechanosensory Protein
The α-catenin of adherens junctions is an allosteric protein with three VH (vinculin homology) domains...
Non-Canonical Wnt Signaling Pathways
