title: Dynamic imaging of the growth plate cartilage reveals multiple contributors to skeletal morphogenesis.
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.
authors: Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA.|Department of Molecular and Computational Biology, University of Southern California, Los Angeles, California, USA.|Developmental Biology and Regenerative Medicine Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California 90027, USA.
authors: Yuwei
authors: Y
authors: Li
authors: Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA.|Department of Molecular and Computational Biology, University of Southern California, Los Angeles, California, USA.
authors: Vikas
authors: V
authors: Trivedi
authors: Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA.|Department of Molecular and Computational Biology, University of Southern California, Los Angeles, California, USA.
authors: Thai V
authors: TV
authors: Truong
authors: Department of Radiology, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California 90027, USA.
authors: David S
authors: DS
authors: Koos
authors: Department of Radiology, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California 90027, USA.
authors: Rusty
authors: R
authors: Lansford
authors: Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
authors: Cheng-Ming
authors: CM
authors: Chuong
authors: Developmental Biology and Regenerative Medicine Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California 90027, USA.
authors: David
authors: D
authors: Warburton
authors: Department of Radiology, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California 90027, USA.
authors: Rex A
authors: RA
authors: Moats
authors: Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA.|Department of Molecular and Computational Biology, University of Southern California, Los Angeles, California, USA.|Developmental Biology and Regenerative Medicine Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California 90027, USA.|Department of Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, California, USA.
authors: Scott E
authors: SE
authors: Fraser
mesh_terms: D000818:Animals; D002356:Cartilage / Q000196:embryology / Q000378:metabolism / Q000648:ultrastructure*; D002455:Cell Division; D002465:Cell Movement; D048429:Cell Size; D002642:Chick Embryo; D019902:Chondrocytes / Q000378:metabolism / Q000648:ultrastructure*; D005109:Extracellular Matrix / Q000737:chemistry / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism / Q000648:ultrastructure*; D015870:Gene Expression; D017930:Genes, Reporter; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006132:Growth Plate / Q000196:embryology / Q000378:metabolism / Q000648:ultrastructure*; D050279:Metacarpal Bones / Q000196:embryology / Q000378:metabolism / Q000648:ultrastructure*; D018613:Microscopy, Confocal; D009924:Organ Culture Techniques; D010012:Osteogenesis / Q000502:physiology*; D017785:Photons; D012190:Retroviridae / Q000235:genetics; D059008:Time-Lapse Imaging
chemical_list: D049452:Green Fluorescent Proteins