Cell adhesion clustering with

Many transmembrane proteins that mediate intracellular signaling form complexes with both intra- and extracellular proteins. For example, neural cell adhesion molecules (NCAMs) are cell-surface glycoproteins (Ch. 7). The extracellular domains of NCAMs can activate fibroblast growth factor receptors when clustered by reaction with NCAM antibodies [4] or by homotypic binding to domains of adjacent cells (see Fig. 7-2). Activation was found to sequester a complex of NCAM, (31 spectrin and PKC(32 into rafts, as defined by the operational criteria discussed on p. 28. 

It has been proposed that cardiac Na channels may be targeted and clustered to specific locations in a similar manner to that observed for Na channels in brain (Cohen 1996). The presence of j subunits in cardiac myocytes may facilitate Na channel locahzation and clustering to discrete functional domains via homophilic or heterophihc cell adhesion interactions. Interestingly, treatment of inside-out patches of ventricular cells with cytochalasin-D induced Na channels to enter a mode characterized by lower peak open probability with a greater persistent activity, consistent with a decrease in the rate of inactivation (Undrovinas et al... 

Integrins cluster into adhesive structures with various morphologies in nonepithelial cells. Immunofluorescence methods were used to detect adhesive structures (green) on cultured cells. 

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