Fig. 3

Phosphorylated Akt (p-Akt) is relocated to caveolae in osteogenically differentiating MSCs. a A modified sucrose gradient flotation method [43] was used to separate membrane rafts with different buoyancies to distinguish noncaveolar membrane rafts from caveolae. b Cav-1 protein was detected by immunoblotting in the middle fractions of the gradient, indicating the presence of caveolae. c, d p-Akt was much more abundant in the noncaveolar membrane raft fractions. c No p-Akt was detected in the caveolar fraction of MSCs cultured in standard growth medium (GM). d However, p-Akt was detected in the caveolar fraction of MSCs cultured in the presence of osteogenic supplements for 10 days (OM). These results suggest that a portion of p-Akt relocated to caveolae during osteogenesis. Molecular weight standards are indicated on the right of the immunoblot panels. Data shown are representative of three replicates