Transient expression of adheron molecules during chick retinal development.
Neuritogenesis and synapse formation are transient phenomena mediated in part by filopodial attachments (Tsui, Lankford, and Klein, Proc. Natl. Acad. Sci. 82:8256-8260 1985). The attachments can be labeled by antisera against adherons, adhesive microparticles isolated from cell culture media (Tsui, Schubert, and Klein, J. Cell Biol. 106:2095-2108 1988). Here, two monoclonal antibodies raised against adherons have been found to recognize transiently expressed membrane antigens of developing avian retina. Early in development, monoclonal antibody (mAb) AD1 stained antigens that spanned the entire tissue. With time, immunoreactivity became restricted to optic fiber, ganglion cell, and inner plexiform layers. Immunoblots of embryonic day (E) 13 retina showed a broad band at 66-72 kD for particulate fractions and a fine band at 70 kD for soluble fractions. The particulate forms disappeared as retinas matured, but the soluble form did not. mAb AD2 initially labeled retina antigens of optic fiber, ganglion cell, and inner plexiform layers (IPL). Labeling in the plexiform layer showed discrete lamina. Immunoreactivity first appeared at E9, peaked at E15, and then disappeared shortly after hatching. In isolated cells, AD2 labeled small cell surface aggregates. Cytoarchitectural studies, using whole-mount transmission electron microscopy, showed AD2 antigen in cell surface microfilaments, including some that joined filopodia together. The adheron antigens recognized by mAbs AD1 and AD2 thus were (1) topographically restricted; (2) associated with cell surfaces; and (3) developmentally down-regulated. This pattern suggests a role in developmentally transient cell surface phenomena, such as neurite extension or junction biogenesis.
Tsui
H C
HC
Department of Neurobiology and Physiology, Northwestern University Institute for Neuroscience, Evanston, Illinois 60208.
Pope
W B
WB
Kim
C S
CS
Klein
W L
WL
D000818:Animals; D000911:Antibodies, Monoclonal; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects; D005260:Female; D006735:Horseradish Peroxidase; D006825:Hybridomas; D006863:Hydrogen-Ion Concentration; D015151:Immunoblotting; D007150:Immunohistochemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D016501:Neurites / Q000187:drug effects; D010206:Papain; D012160:Retina / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D012965:Sodium Chloride / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects
D000911:Antibodies, Monoclonal; D015816:Cell Adhesion Molecules, Neuronal; D012965:Sodium Chloride; D006735:Horseradish Peroxidase; D010206:Papain