FIGURE 4.

Effects of ARAP2 or ACAP1 knockdown on traffic of transferrin and EGFR. A and B, transferrin (Tfn) recycling. Transferrin-Alexa Fluor 488 was internalized in siRNA-treated HeLa cells at 37 °C for 30 min. Cells were washed and incubated in fresh media for the indicated times. Cells were put on ice, and internal transferrin-Alexa Fluor 488 was measured by flow cytometry. C and D, EGFR degradation. siRNA-treated HeLa cells were serum-starved overnight and subsequently treated with EGF for the indicated times. Cells were lysed, and EGFR levels were determined by anti-EGFR immunoblot analyses. Quantifications by densitometry analysis from three experiments (mean ± S.E.) are shown.