Figure 9.

Expression of Rac1N17 inhibits the selective disassembly of the I-Z-I segments induced by v-Src in myotubes. QMb-LA29 transiently transfected with expression vectors encoding for β-galactosidase (A and B) and myc epitope–tagged Rac1N17 (C and D) were allowed to differentiate in DM at 41°C for 3 d and then shifted to 35°C for 4 h. Confocal micrographs of myotubes double labeled with phallacidin (A and C) and antibodies to β-galactosidase (B) or the myc epitope (D) show that Rac1N17 inhibits the v-Src–induced formation of actin bodies apparent in control cultures. Bar, 10 μm.