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Updated: Jun 24, 2026
04:48
Generation of Induced Pluripotent Stem Cell-Derived iTenocytes via Combined Scleraxis Overexpression and 2D Uniaxial Tension
Published on: March 1, 2024
The basic helix-loop-helix transcription factor scleraxis regulates fibroblast collagen synthesis
Leon Espira1, Lise Lamoureux, Stephen C Jones
1Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, University of Manitoba, 351 Tache Avenue, Winnipeg, Manitoba, Canada.
Journal of Molecular and Cellular Cardiology
|April 14, 2009
Summary
Scleraxis, a transcription factor, is newly found to regulate collagen gene expression in the heart. Its increased expression in cardiac fibroblasts and post-infarct scars suggests a role in heart tissue development and repair.
Area of Science:
- Cardiovascular Biology
- Molecular Biology
- Fibrosis Research
Background:
- Scleraxis (SCX) is known to regulate collagen-rich tissues like tendons and cardiac valves.
- Its role in general cardiac collagen synthesis remains largely unknown.
Purpose of the Study:
- To investigate the role of scleraxis in cardiac collagen synthesis.
- To determine if scleraxis regulates collagen I alpha 2 (COL1A2) gene expression in cardiac fibroblasts.
Main Methods:
- Real-time PCR to measure scleraxis mRNA levels.
- Adenoviral gene delivery for scleraxis overexpression.
- Luciferase reporter assays to assess promoter activity.
Main Results:
- Scleraxis mRNA is upregulated by TGF-beta(1) and fibroblast-to-myofibroblast phenoconversion.
- Scleraxis overexpression significantly increases COL1A2 gene expression.
- Scleraxis transactivates the COL1A2 promoter in a DNA-binding dependent manner.
- Scleraxis expression is markedly increased in infarcted rat heart scar tissue.
Conclusions:
- Scleraxis plays a novel role in regulating cardiac collagen gene expression.
- Scleraxis is involved in post-infarct scar formation in the heart.
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