Fig. 4. Cellular structures and functions other than the Golgi apparatus are not markedly affected by the expression of RGSZ1. A plasmid for 6xHis-RGSZ1 was transfected into HeLa cells. At 14 hours after transfection, the cells were fixed, and then processed for indirect immunofluorescence. The panels show the localization of tubulin (a), NADH-cytochrome P-450 reductase (FP2; c), and FITC-transferrin (Tf-FITC; e). For the FITC-transferrin uptake experiment, HeLa cells transfected with 6xHis-RGSZ1 were incubated with FITC-transferrin at 37°C for 1 hour. The cells were then processed for immunofluorescence. 6xHis-RGSZ1-expressing cells were detected with the anti-tetra-His antibody (b,d,f). Arrows indicate RGSZ1-expressing cells. Bar, 20 µm.