SCF-induced cell spreading of BMMCs on fibronectin is independent of Lyn/Fgr/Hck kinases. (A) BMMCs from lyn^+/+, lyn^−/−, lyn/fgr/hck^−/− mice were plated on fibronectin-coated coverslips in the presence of SCF (20 ng/mL) for 15 or 45 minutes. Cells were fixed, permeabilized, and stained with TRITC-phalloidin. Representative fluorescence microscopy images are shown. (B) Cell spreading and lamellipodia formation of SCF-treated BMMCs (20 ng/mL for 45 minutes; mean ± SD; n = 100) plated on fibronectin-coated wells were analyzed by light microscopy.