Characterization of axonally transported glycoproteins in regenerating garfish olfactory nerve.
This study examined changes in composition and concanavalin A (Con A) binding of axonally transported glycoproteins and their pronase-generated glycopeptides in regenerating garfish olfactory nerve. A previous study had demonstrated a regeneration-related increase in the proportion of [3H]glucosamine label in lower-molecular-weight Con A-binding glycopeptides derived from transported glycoproteins. Further analysis of carbohydrate composition shows that these molecules resemble mannose-rich oligosaccharides in composition and are increased in absolute amount in regenerating nerve. Subcellular analysis shows that the Con A-binding glycopeptides are enriched in membrane subfractions, particularly in a high-density fraction that morphologically resembles isolated cell surface coat. Regeneration-related changes in intact axonally transported glycoproteins were also detected. Sodium dodecyl sulfate gel electrophoresis of transport-labeled glycoproteins disclosed growth-correlated increases in radioactivity associated with 180-200K, 105-115K, and 80-90K components, while a 150-160K molecular weight class of glycoproteins was diminished in relative labeling. Intact glycoproteins displaying an affinity for Con A were also augmented in regenerating nerve, the increases occurring primarily in molecules in the 50-140K range.
D000818:Animals; D001369:Axons / Q000378:metabolism*; D001692:Biological Transport; D003208:Concanavalin A / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005399:Fishes; D006023:Glycoproteins / Q000378:metabolism*; D006595:Hexosamines / Q000032:analysis; D009416:Nerve Regeneration; D009832:Olfactory Nerve / Q000378:metabolism*
D006023:Glycoproteins; D006595:Hexosamines; D003208:Concanavalin A