FIG. 9.

mTOR is a specific mediator of IGF-1R action during keratinocyte differentiation. (A) IGF-1R inactivation was carried out as described as described in the legend for Fig. 1. Thereafter, cells were treated with rapamycin (20 nM) and induced to differentiate for 48 h as detailed in the text. Analysis of differentiation marker expression was carried as described in the legend for Fig. 5. Actin levels are shown and demonstrate equal loading. Samples of each independent experiment were run on the same gel and blotted together. The blots of loricrin and K1 were further analyzed by scanning densitometry (B). Results are a summary (means ± standard errors) of three separate experiments and are expressed in arbitrary units. **, P < 0.01 for IGF-1R KO (M and H) DMSO treated versus (M and H) IGF-1R KO treated with rapamycin.