The glucose polymer of PC12 cells is susceptible to trypsinization.

The glucose polymer of PC12 cells (Rasilo, M.-L. and Yamagata, T., 1988, FEBS Letters 227, 191-194 and Rasilo, M.-L. and Yamagata, T., 1988, Journal of Biochemistry, 104, 742-754) was found to be located on the cell surface. The polymer was liberated from the galactose-labeled cells with a trypsin treatment: maximally 65% of the glucose polymer was liberated, compared with 36% of the large glycopeptides. Even when the cells were incubated with the saline about one fourth of the polymer moved into the solution, but less than 8% of the large glycopeptides. Phosphatidyl inositol-specific phospholipase C failed to liberate the polymer.