Early- and late-migrating cranial neural crest cell populations have equivalent developmental potential in vivo.
We present the first in vivo study of the long-term fate and potential of early-migrating and late-migrating mesencephalic neural crest cell populations, by performing isochronic and heterochronic quail-to-chick grafts. Both early- and late-migrating populations form melanocytes, neurons, glia, cartilage and bone in isochronic, isotopic chimeras, showing that neither population is lineage-restricted. The early-migrating population distributes both dorsally and ventrally during normal development, while the late-migrating population is confined dorsally and forms much less cartilage and bone. When the late-migrating population is substituted heterochronically for the early-migrating population, it contributes extensively to ventral derivatives such as jaw cartilage and bone. Conversely, when the early-migrating population is substituted heterochronically for the late-migrating population, it no longer contributes to the jaw skeleton and only forms dorsal derivatives. When the late-migrating population is grafted into a late-stage host whose neural crest had previously been ablated, it migrates ventrally into the jaws. Thus, the dorsal fate restriction of the late-migrating mesencephalic neural crest cell population in normal development is due to the presence of earlier-migrating neural crest cells, rather than to any change in the environment or to any intrinsic difference in migratory ability or potential between early- and late-migrating cell populations. These results highlight the plasticity of the neural crest and show that its fate is determined primarily by the environment.
Baker
C V
CV
Division of Biology, Beckman Institute 139-74, California Institute of Technology, Pasadena 91125, USA.
Bronner-Fraser
M
M
Le Douarin
N M
NM
Teillet
M A
MA
D000818:Animals; D019521:Body Patterning / Q000502:physiology*; D001842:Bone and Bones / Q000196:embryology; D002356:Cartilage / Q000196:embryology; D002465:Cell Movement / Q000502:physiology*; D002642:Chick Embryo; D003370:Coturnix; D003391:Cranial Nerves / Q000196:embryology; D004475:Ectoderm / Q000166:cytology; D005726:Ganglia, Parasympathetic / Q000196:embryology; D008544:Melanocytes / Q000166:cytology; D008636:Mesencephalon / Q000166:cytology / Q000196:embryology*; D009432:Neural Crest / Q000166:cytology* / Q000196:embryology* / Q000637:transplantation; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000166:cytology; D019170:Somites; D018183:Transplantation Chimera; D012668:Trigeminal Ganglion / Q000196:embryology