NCAM induces sustained signaling. Lysates from HeLa cells stimulated for the indicated time intervals with FGF-2 (left), FGL (middle), or NCAM-Fc (right) were immunoblotted for phospho–FRS-2α, phospho-Akt, phospho-Src, phospho-Shc, or phospho-Erk1/2 followed by immunoblotting for total FRS-2α, Akt, Src, Shc, or total Erk1/2 as indicated.