Dynamic imaging of the growth plate cartilage reveals multiple contributors to skeletal morphogenesis

Nat Commun. 2015 Apr 13;6:6798. doi: 10.1038/ncomms7798.

Abstract

The diverse morphology of vertebrate skeletal system is genetically controlled, yet the means by which cells shape the skeleton remains to be fully illuminated. Here we perform quantitative analyses of cell behaviours in the growth plate cartilage, the template for long bone formation, to gain insights into this process. Using a robust avian embryonic organ culture, we employ time-lapse two-photon laser scanning microscopy to observe proliferative cells' behaviours during cartilage growth, resulting in cellular trajectories with a spreading displacement mainly along the tissue elongation axis. We build a novel software toolkit of quantitative methods to segregate the contributions of various cellular processes to the cellular trajectories. We find that convergent-extension, mitotic cell division, and daughter cell rearrangement do not contribute significantly to the observed growth process; instead, extracellular matrix deposition and cell volume enlargement are the key contributors to embryonic cartilage elongation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cartilage / embryology
  • Cartilage / metabolism
  • Cartilage / ultrastructure*
  • Cell Division
  • Cell Movement
  • Cell Size
  • Chick Embryo
  • Chondrocytes / metabolism
  • Chondrocytes / ultrastructure*
  • Extracellular Matrix / chemistry
  • Extracellular Matrix / metabolism
  • Fibroblasts / metabolism
  • Fibroblasts / ultrastructure*
  • Gene Expression
  • Genes, Reporter
  • Genetic Vectors
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Growth Plate / embryology
  • Growth Plate / metabolism
  • Growth Plate / ultrastructure*
  • Metacarpal Bones / embryology
  • Metacarpal Bones / metabolism
  • Metacarpal Bones / ultrastructure*
  • Microscopy, Confocal
  • Organ Culture Techniques
  • Osteogenesis / physiology*
  • Photons
  • Retroviridae / genetics
  • Time-Lapse Imaging

Substances

  • Green Fluorescent Proteins