Cell surface proteins of cultured brain cells and their recognition by anti-cerebellum (anti-NS-4) antiserum.

Abstract

Abstract— Surface proteins of cultured young postnatal mouse cerebella and embryonic mouse cerebral hemispheres were identified by Iactoperoxidase‐catalysed radioiodination and by their interaction with an anti‐mouse cerebellum antiserum (anti‐NS‐4 serum) which recognizes surface components on brain cells. Several (8 10) iodinated polypeptides are recognized by radioautography after polyacrylamide gel electrophoresis. Their surface location was confirmed by their sensitivity to mild trypsin treatment on intact cells. Iodinated polypeptides from cells of non‐nervous tissues showed a different gel pattern. Immuno‐precipitates of solubilizcd surface‐iodinated cerebellar cells with anti‐NS‐4 serum contained two prominent labeled proteins with apparent molecular weights of 200 × 103 and 145 × 103. These proteins were also biosynthetically labeled with [3H]leucine. The 145 × 103 molecular weight component was also found in immunoprecipitates prepared from embryonic cerebral cells, but the 200 × 103 molecular weight component was replaced by a broad peak with an apparent molecular weight of around 250 × 103.