Forced expression of ARHGAP22 does not affect endocytic trafficking of transferrin.

<p>A7 cells were either not transfected (control) or transfected with HA-ARHGAP22. After 24 h, the cells were incubated in serum-free growth medium for 1 h. The cells were then incubated with 20 µg/ml Alexa Fluor 568-transferrin at 37°C for 30 min and fixed immediately after incubation. Cells were stained with antibodies for Rab11 or HA-ARHGAP22 (green). Internalized transferrin signals (red) were detected in the fixed cells. Merged fluorescent images are shown. The cells were also stained with hoechst 33258 for nuclei (blue). Scale bar, 20 µm. (<b>B</b>) Quantification of the internalized transferrin signal. The transferrin intensity was calculated as fluorescence intensity of Alexa Fluor 568-transferrin per cell divided by the surface area of this cell. The fluorescence intensity and cell area were measured by ImageJ (NIH), and the data are expressed as the mean ± s.e.m. (n = 50 cells). Statistical significance was determined by Student's <i>t</i>-test.