Fig. 8. Activated Rac1 does not induce stable lamellipodia in the absence of 3ß1. MK^–/– cells were infected with adenovirus encoding either Rac1L61 (A,B,E-G) or a GFP control (C,D). Infected cells were plated on LN-5 ECM and stained for either F-actin with TRITC-conjugated phalloidin (A,C) or the Myc epitope (F). Infected cells were visualized by GFP fluorescence. Bar, 10 µm. (H) Cell lysates from Rac1L61-infected or control-infected cells were immunoblotted for Myc epitope or GFP.