Neural cell adhesion molecules modulate tyrosine phosphorylation of tubulin in nerve growth cone membranes.
Triggering neural cell adhesion molecules of the immunoglobulin superfamily with specific ligands or antibodies inhibited the phosphorylation of tryosyl residues in a subpopulation of alpha- and beta-tubulin associated with membranes from a subcellular fraction of nerve growth cones from fetal rat brain. Preincubation of these membranes with purified extracellular fragments of L1, N-CAM, or myelin-associated glycoprotein, or with antibodies directed against the extracellular domains of L1 or N-CAM, inhibited pp60c-src-dependent phosphorylation of tubulin in an endogenous membrane kinase reaction. Other proteins that affect neurite outgrowth (fibronectin, laminin, antibodies against N-cadherin) had no effect. The results suggest that cell adhesion molecules transduce cell surface events to intracellular signals by modulating the activity of protein tyrosine kinases or phosphatases in axonal membranes to influence cytoskeletal dynamics at the growth cone.
Atashi
J R
JR
Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill 27599-7260.
Klinz
S G
SG
Ingraham
C A
CA
Matten
W T
WT
Schachner
M
M
Maness
P F
PF
D000818:Animals; D000911:Antibodies, Monoclonal; D001921:Brain / Q000196:embryology / Q000378:metabolism* / Q000648:ultrastructure; D015820:Cadherins / Q000276:immunology / Q000502:physiology; D015816:Cell Adhesion Molecules, Neuronal / Q000276:immunology / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005353:Fibronectins / Q000494:pharmacology; D007140:Immunoglobulin Fab Fragments; D007797:Laminin / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure; D010766:Phosphorylation; D019000:Phosphotyrosine; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D015398:Signal Transduction; D014404:Tubulin / Q000378:metabolism*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D015820:Cadherins; D015816:Cell Adhesion Molecules, Neuronal; D005353:Fibronectins; D007140:Immunoglobulin Fab Fragments; D007797:Laminin; D014404:Tubulin; D019000:Phosphotyrosine; D014443:Tyrosine; D016392:Proto-Oncogene Proteins pp60(c-src)