title: Beyond cell proliferation in avian facial morphogenesis.
abstract: The upper jaw in vertebrates forms from several prominences that arise around the stomodeum or primitive mouth. These prominences undergo coordinated growth and morphogenesis to fuse and form the face. Undirected, regionalized cell proliferation is thought to be the driving force behind the morphogenesis of the facial prominences. However, recent findings suggest that directed cell behaviors in the mesenchyme (e.g., directed cell division, directed cell movement, convergent extension) might be required for successful face formation. Here we discuss the evidence for this view and how directed behaviors may interact with the basement membrane to regulate morphogenesis of the facial region. We believe that future research in these largely unexplored areas could significantly impact our understanding of facial morphogenesis.
authors.affiliation: Department of Orthopaedic Surgery, San Francisco General Hospital, Orthopaedic Trauma Institute, University of California, San Francisco, California.
authors.forename: Marta
authors.initials: M
authors.lastname: Linde-Medina
authors.affiliation: Department of Anatomy and Cell Biology, University of Calgary, McCaig Institute for Bone and Joint Health, Calgary, Alberta, Canada.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Hallgrímsson
authors.affiliation: Department of Orthopaedic Surgery, San Francisco General Hospital, Orthopaedic Trauma Institute, University of California, San Francisco, California.
authors.forename: Ralph
authors.initials: R
authors.lastname: Marcucio
mesh_terms: D000818:Animals; D001717:Birds / Q000196:embryology*; D005145:Face / Q000196:embryology*; D009024:Morphogenesis / Q000502:physiology*
keywords: basement membrane; budding outgrowth; directed cell behaviors; epithelial evaginations