ZFIN ID: ZDB-PUB-181127-80
Mechanical force regulates tendon extracellular matrix organization and tenocyte morphogenesis through TGFbeta signaling
Subramanian, A., Kanzaki, L.F., Galloway, J.L., Schilling, T.F.
Date: 2018
Source: eLIFE   7: (Journal)
Registered Authors: Galloway, Jenna, Schilling, Tom, Subramanian, Arul
Keywords: cell biology, developmental biology, zebrafish
MeSH Terms:
  • Animals
  • Animals, Genetically Modified
  • Cell Shape
  • Extracellular Matrix/metabolism*
  • Genes, Reporter
  • Luminescent Proteins/analysis
  • Luminescent Proteins/genetics
  • Morphogenesis*
  • Recombinant Fusion Proteins/analysis
  • Recombinant Fusion Proteins/genetics
  • Signal Transduction*
  • Stress, Mechanical*
  • Tendons/physiology*
  • Tenocytes/cytology*
  • Tenocytes/physiology
  • Transforming Growth Factor beta/metabolism*
  • Zebrafish
PubMed: 30475205 Full text @ Elife
Mechanical forces between cells and extracellular matrix (ECM) influence cell shape and function. Tendons are ECM-rich tissues connecting muscles with bones that bear extreme tensional force. Analysis of transgenic zebrafish expressing mCherry driven by the tendon determinant scleraxis reveals that tendon fibroblasts (tenocytes) extend arrays of microtubule-rich projections at the onset of muscle contraction. In the trunk, these form a dense curtain along the myotendinous junctions at somite boundaries, perpendicular to myofibers, suggesting a role as force sensors to control ECM production and tendon strength. Paralysis or destabilization of microtubules reduces projection length and surrounding ECM, both of which are rescued by muscle stimulation. Paralysis also reduces SMAD3 phosphorylation in tenocytes and chemical inhibition of TGFβ signaling shortens tenocyte projections. These results suggest that TGFβ, released in response to force, acts on tenocytes to alter their morphology and ECM production, revealing a feedback mechanism by which tendons adapt to tension.