FIGURE 1.

Overexpression of CA-Rac-GFP or Tiam1-GFP stimulates GLUT4 translocation to the membrane of muscle cells. A and B, GLUT4myc myoblasts were transfected with GFP, WT-Rac-GFP, or CA-Rac-GFP followed by stimulation with/without insulin for 10 min to measure changes in surface GLUT4myc and quantified relative to GFP basal signal (mean ± S.E. (error bars); *, p < 0.05). C, myoblasts transfected with GFP, CA-Rac-GFP, or Tiam1-GFP were permeabilized and stained with rhodamine-phalloidin to visualize changes in F-actin. D and E, GLUT4myc myoblasts expressing GFP or Tiam1-GFP were stimulated with/without insulin for 10 min followed by staining for surface GLUT4myc and quantification relative to GFP basal signal (mean ± S.E. (error bars); *, p < 0.05). Representative images of three independent experiments are shown. Bar, 10 μm.