MOLECULAR ASSOCIATION OF THE NEURAL ADHESION MOLECULES L1 AND N-CAM IN THE SURFACE-MEMBRANE OF NEUROBLASTOMA-CELLS IS SHOWN BY CHEMICAL CROSS-LINKING

The two neural cell adhesion molecules Ll and N-CAM could be shown to be associated in the surface membrane of cultured neuroblastoma cells by chemical cross-linking with 3,3'-dithiobis(sulphosuccinimidyl-propionate) and subsequent immunopurification and precipitation using antibodies to Ll and N-CAM. Glycoproteins recognized in neuroblastoma cells by antibodies to mouse liver membranes were not chemically cross-linked to Ll or N-CAM. These observations suggest that a molecular association between the two molecules may be the basis for their functional cooperativity (Kadmon et al., 1990a,b, J. Cell Biol., 110,193-208;209-218).