Fig. 9. TFN uptake is not inhibited by N4WBP5A overexpression. TFN uptake was performed in HeLa cells transfected with myc-N4WBP5A for 20 (A-C) and 40 minutes (D-F). Cells were serum starved for 2 hours and cultured with TFN-Alexa Fluor 594 (10 µg/ml, red) for 30 minutes at 4°C and TFN uptake was performed at 37°C for up to 20 and 40 minutes. Surface-bound TFN-Alexa Fluor 594 was stripped, cells were fixed and permeabilized and immunohistochemistry performed with an anti-myc antibody and secondary antibody conjugated to Alexa Fluor 488. The figure shows endocytosed TFN-Alexa Fluor 594 (A,D), myc-N4WBP5A transfected cells (B,E) and merged images (C,F). Bar, 20 µm.