Localization of the L2 monoclonal antibody binding site on chicken neural cell adhesion molecule (NCAM) and evidence for its role in NCAM-mediated cell adhesion

Abstract

Recent studies have described the localization of functional and structural domains on the neural cell adhesion molecule NCAM. In the present study we have extended these observations to examine the location of the carbohydrate epitope recognized by the L2 monoclonal antibody. This carbohydrate moiety is localized to the 65,000-dalton amino-terminal fragment of NCAM (previously designated FrI), but is not present in the amino-terminal 25,000-dalton region of NCAM that contains the heparin-binding domain. We have also examined the role of this domain in NCAM-mediated cell adhesion, and have shown that incubation of an NCAM substratum with L2 monoclonal antibody inhibits cell attachment to this substratum. These data therefore suggest that the carbohydrate moiety recognized by L2 monoclonal antibody may be involved in the modulation of NCAM-mediated cell adhesion.