Changes in the expression of fibroblast growth factor receptors mark distinct stages of chondrogenesis in vitro and

G Szebenyi1, M P Savage, B B Olwin

  • 1Department of Anatomy, University of Wisconsin Medical School, Madison 53706, USA.

Insights

Fibroblast growth factor receptors (FGFRs) are crucial for limb skeleton development. Their changing expression during cartilage differentiation in mesenchymal cells marks distinct developmental stages.

Area of Science:

  • Developmental biology
  • Skeletal biology
  • Molecular biology

Background:

  • Fibroblast growth factors (FGFs) and their receptors (FGFRs) regulate limb skeletal patterning and growth.
  • Aberrant FGF/FGFR signaling or mutations cause skeletal disorders.

Purpose of the Study:

  • To investigate the role of FGFR expression changes in cartilage differentiation.
  • To correlate FGFR mRNA expression with specific stages of limb skeletal development.

Main Methods:

  • Mesenchymal micromass cultures were used to mimic in vitro cartilage differentiation.
  • In ovo studies were conducted to observe FGFR expression in developing embryos.
  • Quantitative analysis of FGFR 1, 2, and 3 mRNA expression was performed at different developmental stages.

Main Results:

  • FGFR 1 mRNA was predominantly found in undifferentiated, proliferating mesenchyme.
  • FGFR 2 mRNA localized to precartilage cell aggregates.
  • FGFR 3 mRNA was enriched in differentiating cartilage nodules.

Conclusions:

  • Changes in FGFR 1, 2, and 3 mRNA expression are intrinsic to cartilage differentiation.
  • These expression patterns correlate with distinct phases of cartilage patterning in vitro and in ovo.
  • FGFR expression dynamics mark specific developmental stages in limb skeleton formation.

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