Delineation of olfactory pathways in the frog nervous system by unique glycoconjugates and N-CAM glycoforms.

The olfactory neuroepithelium, which contains the primary sensory olfactory neurons, continually undergoes neurogenesis and axonal outgrowth throughout life. We describe here several new olfactory system-specific glycoforms of the neural cell adhesion molecule N-CAM in the frog, R. catesbeiana. Using immunochemical methods for in situ localization, we show that the lectin dolichos biflorus agglutinin (DBA) and two monoclonal antibodies, 9OE and 3A6, detect three unique N-CAM forms present on primary sensory olfactory axons. In addition, DBA and monoclonal antibody 9OE recognize glycoconjugates and/or N-CAM glycoforms expressed specifically in discrete central olfactory pathways and regions in frog brain. This is a novel example of unique adhesion molecule forms present in a chain of two neurons within a vertebrate neural pathway. Together these glycoconjugates and N-CAM glycoforms may participate in cellular interactions associated with olfactory system pathway formation and renewal.