Nerve growth cone migration onto Schwann cells involves the calcium-dependent adhesion molecule, N-cadherin.
The role of calcium-dependent adhesion molecules in the migration of nerve growth cones onto the top of Schwann cells was probed by examination of sensory growth cone-Schwann cell interactions in medium containing either 1.0 mM Ca2+ or 0.1 mM Ca2+. In the presence of 1.0 mM Ca2+ growth cones rapidly migrated onto Schwann cells, spread, and remained for extended periods. However, in 0.1 mM Ca2+ growth cones still made frequent contacts with Schwann cells, but migration onto the upper cell surface was much reduced. This contrast in growth cone-Schwann cell interactions could be switched rapidly by changing the Ca2+ concentration of the culture medium. Growth cones of retinal neurons showed similar calcium-dependence in their migration onto Schwann cells. Antibodies to the calcium-dependent adhesion molecule, N-cadherin, also blocked growth cone migration onto Schwann cells, but antibodies to another neuronal adhesion molecule, L1, had no effect on growth cone-Schwann cell interactions. Immunocytochemical staining for N-cadherin and L1 indicated that growth cones and Schwann cells have N-cadherin on their surfaces, while L1 is present only on axons and growth cones. These results provide two kinds of evidence that N-cadherin is important in the initial interactions of growth cones and Schwann cells.
Letourneau
P C
PC
Department of Cell Biology and Neuroanatomy, University of Minnesota, Minneapolis 55455.
Shattuck
T A
TA
Roche
F K
FK
Takeichi
M
M
Lemmon
V
V
D000818:Animals; D001369:Axons / Q000187:drug effects / Q000648:ultrastructure*; D002118:Calcium / Q000494:pharmacology*; D015816:Cell Adhesion Molecules, Neuronal / Q000276:immunology / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D002642:Chick Embryo; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology*; D008854:Microscopy, Electron; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D012583:Schwann Cells / Q000166:cytology / Q000502:physiology*; D014741:Video Recording
D015816:Cell Adhesion Molecules, Neuronal; D002118:Calcium