A REQUIREMENT FOR CAVEOLIN-1 AND ASSOCIATED KINASE FYN IN INTEGRIN SIGNALING AND ANCHORAGE-DEPENDENT CELL-GROWTH

Caveolin-l functions as a membrane adaptor to link the integrin cw sub unit to the tyrosine kinase Fyn. Upon integrin ligation, Fyn is activa ted and binds, via its SH3 domain, to Shc. Shc is subsequently phospho rylated at tyrosine 317 and recruits Grb2. This sequence of events is necessary to couple integrins to the Ras-ERK pathway and promote cell cycle progression. These findings reveal an unexpected function of cav eolin-l and Fyn in integrin signaling and anchorage-dependent cell gro wth.