The axonal recognition molecule F11 is a multifunctional protein: specific domains mediate interactions with Ng-CAM and restrictin.
F11 is a glycosyl phosphatidylinositol-anchored axonal surface glycoprotein belonging to a neural subgroup of the immunoglobulin superfamily. In this report, we demonstrate that the F11 protein displays three distinguishable activities: binding to the cell recognition molecule Ng-CAM, interaction with the extracellular matrix glycoprotein restrictin (RN), and a neurite outgrowth-promoting activity. By analyzing deletion mutants expressed in transfected COS cells, epitope mapping of monoclonal antibodies, and neurite outgrowth assays, we reveal that these activities can be localized to distinct regions within the F11 protein. The Ng-CAM-binding site resides in the first two immunoglobulin-like domains of F11, whereas the RN-binding site resides in the second or third domain. A neurite outgrowth-promoting activity of F11 characterized by in vitro culture of tectal cells is independent of F11-Ng-CAM and F11-RN binding.
Brümmendorf
T
T
Max-Planck-Institut für Entwicklungsbiologie, Tübingen, Federal Republic of Germany.
Hubert
M
M
Treubert
U
U
Leuschner
R
R
Tárnok
A
A
Rathjen
F G
FG
D000818:Animals; D001665:Binding Sites; D015816:Cell Adhesion Molecules, Neuronal / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D002461:Cell Line, Transformed; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D007136:Immunoglobulins / Q000737:chemistry; D039841:Leukocyte L1 Antigen Complex; D008863:Microspheres; D009419:Nerve Tissue Proteins / Q000378:metabolism; D016501:Neurites / Q000187:drug effects / Q000502:physiology; D019063:Tenascin
D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D007136:Immunoglobulins; D039841:Leukocyte L1 Antigen Complex; D009419:Nerve Tissue Proteins; D019063:Tenascin; C074638:tenascin R