Figure 2.

S6K mutation reverses cell shape changes. A, B) The specific subcellular localization of overexpressed myc-tagged S6K plasmids in either RAW264.7 macrophages (A) (shown are two representative examples among 6 different fields) or COS-7 fibroblasts (B). Immunofluorescent signals are from c-myc-FITC or c-myc-TRITC IgG antibodies, respectively. Cells transfected with S6K-WT DNA contained numerous filopodia (white arrowheads), which are less evident in S6K-T389E or -KD expressing cells. C) Schematic drawing of cell shape changes typical of macrophage, neuronal or transformed cancer cell morphology. D, E) Cell circularities of RAW264.7 macrophages and COS-7 cells are significantly affected due to S6K overexpression. Cell circularity was calculated as indicated in Materials and Methods. Data are presented as mean values ± sem from n = 12 cells quantified. *P < 0.05, statistically significant increase, between samples and controls. ^#P < 0.05, statistically significant decrease, between samples and controls.